Subjunctive mood

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Subjunctive mood

In grammar, the subjunctive mood (sometimes referred to as the conjunctive mood) is a verb mood that exists in many languages. It is typically used in dependent clauses to express wishes, commands, emotion, possibility, judgment, necessity, or statements that are contrary to fact at present. The details of subjunctive use vary from language to language.

The subjunctive in Indo-European languages

The reconstructed Proto Indo-European language is the hypothetical parent of many language families. These include the Romance languages, Celtic languages, Germanic languages (including English), Slavic languages, many of the languages of the Indian subcontinent and the Iranian or Persian languages and several others. It had two closely related moods: the subjunctive and the optative. Many of its daughter languages combined or merged these moods.

In Indo-European, the subjunctive was formed by using the full ablaut grade of the root of the verb, and appending the thematic vowel *-e- or *-o- to the root stem, with the full, primary set of personal inflections. The subjunctive was the Indo-European irrealis, used for hypothetical or counterfactual situations.

The optative mood was formed with a suffix *-ieh₁ or *-ih₁ (with a laryngeal). The optative used the clitic set of secondary personal inflections. The optative was used to express wishes or hopes.

Among the Indo-European languages, only Albanian, Avestan, Ancient Greek, Sanskrit, and to some extent Old Church Slavonic kept the subjunctive and optative fully separate and parallel. However, in Sanskrit, use of the subjunctive is only found in the Vedic language of earliest times, and the optative and imperative are in comparison less commonly used. In the later language (from c.500BC), the subjunctive fell out of use, with the optative or imperative being used instead. However, the first person forms of the subjunctive continue to be used, as they are transferred to the imperative, which formerly, like Greek, had no first person forms.

The subjunctive in English

Form

The subjunctive in Modern English is easily distinguished in a great variety of contexts where the sense is past tense, but the form of the subjunctive verb required is present: "It was required that we go to the back of the line." Were it not subjunctive, the form of "to go" for something in the past would have been went. Compare with the non-subjunctive: "Everyone knows that we went to the back of the line."

	Present indicative	Present subjunctive	Past indicative	Past subjunctive
to own (regular verb)	I own he/she/it owns we/you/they own	I own he/she/it own we/you/they own	I owned he/she/it owned we/you/they owned	I owned he/she/it owned we/you/they owned
to be	I am he/she/it is we/you/they are	I be he/she/it be we/you/they be	I was he/she/it was we/you/they were	I were he/she/it were we/you/they were

As shown in the above table, the form of the subjunctive is distinguishable from the indicative in only three circumstances:

in the third person singular of the present tense,
with the verb to be in the present tense, and
in the first person singular and third person singular of verb to be in the past tense.

The modal auxiliaries do not have present subjunctive forms.

In Early Modern English, the past subjunctive was distinguishable from the past indicative not only in the verb to be (as in Modern English) but also in the second-person singular of all verbs. For example: indicative thou sattest, but subjunctive thou sat.

Nevertheless, in some texts in which the pronoun thou is used a final -est or -st is sometimes added; for example, thou beest appears frequently in the work of Shakespeare and some of his contemporaries.

Present and past subjunctive

The terms present subjunctive and past subjunctive can be misunderstood, as they describe forms rather than meanings: the past and present subjunctives are so called because they resemble the past and present indicatives, respectively, but the difference between them is a difference in modality, not a temporal one.

For example, in "I asked that it be done yesterday," be done (a present subjunctive) has no present-tense sense; and likewise, in "If that were true, I'd know it," were (a past subjunctive) has no past-tense sense.

The pluperfect subjunctive

Since the "past subjunctive" is not a true past tense, it uses as its past tense what is structurally its perfect aspect form. This past tense is known as the past perfect subjunctive or pluperfect subjunctive; it is formed using had (the past subjunctive of to have) plus the verb's past participle.

The pluperfect subjunctive is used like the past subjunctive, except that it expresses a past-tense sense. So, for example:

If I had known (yesterday), I would have done something about it.
If I had seen you, I definitely would have said hello.
I wouldn't be here if he hadn't helped me.

When used in the construction of a counterfactual statement as in the examples above, it is paired with the conditional perfect viz. "If I had [not] X, then I would [not] have Y". The (arguably) canonical example of the counterfactual actually eschews the pluperfect subjunctive: If I Knew You Were Comin' I'd've Baked a Cake. This should, of course, be If I Had Known… .

If a clause is in a past tense, then a clause subordinate to it cannot be in the past subjunctive, though it might be in the pluperfect subjunctive; however, if it is in a present tense, then a clause subordinate to it might be in either of the two, depending on meaning.

The pluperfect subjunctive is often replaced with the past subjunctive in colloquial speech, a substitution that is commonly considered incorrect. (See prescription and description.)

(Note that by contrast, the present perfect subjunctive — that he have done — while logically and theoretically possible, is not much used in modern English.)

Future subjunctive

A future subjunctive can be constructed using the conjugated form of the verb "to be" plus the infinitive or with the usage of the modal auxiliary verb "should". Note that the "were" clauses result in the present conditional, while the "should" clauses result in the future indicative. For example:

* If I were to die tomorrow, then you would inherit everything.

* If you were to give the money to me, then I would say no more about it.

* If I should go, then will you feed the hens?

* If he should fall, who will carry the flag in his place?

Construction by inversion

Where the subjunctive is used after “if” in a counterfactual condition (see below), the same effect can be achieved by omitting the “if” and containing the verb and subject.

* If I were the President... / Were I the President...

* If he had a car with him... / Had he a car with him...

Construction using a modal verb

The subjunctive mood can be expressed using the modal verbs shall (should) and may (might).

* Should the teacher come, I will speak with him.

* (May) the Lord bless you and keep you.

* He wrote it in his diary so that he might remember.

The word would (the past tense of "will") can also be used for the past (for example, "He wrote it in his diary so that he would remember"), but it cannot be used in the present or future tense ("Would the teacher come, I will speak with him" is incorrect and confusing).

Usage

As well as being preserved in fossilized phrases, the subjunctive is used in English to express a command, desire, hypothesis, purpose, doubt, or supposition.

Incorrect: If I was you, I would run.

Correct: If I were you, I would run. (The verb follows if and expresses a non-factual condition.)

Incorrect: I wish he was able to type faster.

Correct: I wish he were able to type faster. (The second verb is in a clause following a verb expressing a wish. It also suggests a non-factual or doubtful condition.)

Incorrect: His requirement is that everyone is computer literate.

Correct: His requirement is that everyone be computer literate. (Subordinate clause follows main clause with a demand.)

Incorrect: He recommended that each driver reports his tips.

Correct: He recommended that each driver report his tips.

Sometimes we may use the conditional auxiliary verbs of could, should, or would to express the same sense.

Subjunctive:I wish he were kinder to me. Conditional: I wish he would be kinder to me.

Set phrases

The subjunctive is used in a number of fixed phrases, relics from an older form of the language where it was much more common. Some could be misconstrued as the imperative mood. Common examples are:

* if need be

* as it were

* if I were you; were I you

* be that as it may

* (May God) bless you!

* come Monday (Tuesday, etc.)

* come what may

* (May God) damn it!

* far be it from (or for) me

* till death do us part

* God save our gracious Queen, God bless America, God keep our land glorious and free, God rest ye merry gentlemen, etc.

* (May) Heaven forfend/forbid

* so be it

* suffice it to say

* woe betide

* (May) peace be with you

* long live the king

* the powers that be

* albeit (a synthesis of all be it, i.e. although it be)

* truth be told

* rue the day

* would that it were

* rest in peace

* let (may) it be known

* ...need only..."

To express a command, request, or suggestion

Content clauses expressing commands, requests, or suggestions commonly use the present subjunctive; such a clause may be introduced by a verb like propose, suggest, recommend, move (in the parliamentary sense), demand, or mandate, by an adjective like imperative, important, adamant, or necessary, or by a noun like insistence or proposal.

This use of the subjunctive is known as the mandative subjunctive or the jussive subjunctive and is said to be the most common use of the subjunctive in English. Other authorities say this use is much less common than that in suppositions or hypotheses (e.g. "If she asked for help, I'd help her.") and is often not found in UK English, even in respected news media.

Instead, UK English often uses present indicative or even past indicative − which are both considered incorrect by many people in the UK and (prescriptive) UK authorities on language usage − or a construction with "should". Much time is spent in the UK in trying to prevent this language change well underway in UK English, and the use with "should" is arguably better because not considered as ungrammatical by most. So instead of writing No wonder the Tory Party turned him down as a possible candidate, suggesting he went away and came back with a better public image. as in the Guardian (which would be almost impossible to find in any US newspapers, which would always use the traditional go away and come back), it would be considered less ungrammatical to use should go away. Some authorities like Ernest Gowers even recommend the use with should (in UK English) instead of the untenable traditional forms.

Note that the present subjunctive is used in these cases regardless of the actual time reference (which must be conveyed by the tense of the main verb):

I move(d) that the bill be put to a vote.
I ask(ed) that he be shown mercy.
It is (or was) necessary that we not forget our instructions. / It is (or was) necessary lest we forget our instructions.
Her insistence that he leave seems (or seemed) rude.

Some of these words have two senses: one that introduces a clause in the indicative, and one that introduces a clause in the subjunctive. For example, insist can mean assert forcefully and persistently, in which case it introduces the indicative (He insisted that he was innocent), or it can mean demand forcefully and persistently, in which case it introduces the subjunctive (He insisted that he be given the chance to prove it). This use is typically North American English. The verb in such constructions is sometimes mistakenly believed to be a sort of infinitive, contributing to the notion of the dying subjunctive.

Sometimes the verb of a main clause can be in the subjunctive mood, without any explicit word like the above; this carries the force of a third-person request. This is the usage found in many set expressions, such as God bless you.

* America, America, God shed His grace on thee, and crown thy good with brotherhood ("America the Beautiful")

* God save our gracious Queen

The traditional English text of the Aaronic blessing is cast entirely in the subjunctive, with jussive force:

The Lord bless thee and keep thee. The Lord make his face to shine upon thee. The Lord lift up his countenance upon thee and give thee peace.

To express a wish

The past subjunctive is used after the verb to wish: I wish he were here or I wished he were there. This use of the subjunctive is sometimes known as the "volitional" subjunctive:

* Oh I wish I were in the land of cotton.

To express an hypothesis

The past subjunctive is used after the conjunction if in a contrary-to-fact protasis. For example:

* If I were a millionaire, I would buy a sports car.

* If he had a car with him, he could drive us there.

* If I were a rich man...

In the same vein, the past subjunctive is used following the conjunctions as if and as though to express a contrary-to-fact situation that reality is supposed to resemble:

* She looked as though she were going to kill him, but after glaring for a bit, she just stormed off.

* He tried to explain it — as if he knew anything about the subject!

Note that the past subjunctive is sometimes used in expressing situations that are not necessarily contrary to fact:

* ? I'm torn; if I were to go with choice A, I'd be better off in the short term, but if I were to go with choice B, I might be better off in the long term.

* ? Bring an umbrella; looks as if it were going to rain soon.

To express a purpose

The conjunction lest, indicating a negative purpose, generally introduces a subjunctive clause:

* I eat lest I die.

* I'll place the book back on the shelf, lest it get lost.

The conjunction in order that, indicating a positive purpose, also sometimes introduces a subjunctive clause, though it more commonly introduces a clause using the auxiliary verb may (or in the past tense, might):

* I'm putting your dinner in the oven in order that it (may) keep warm.

* He wrote it in his diary in order that he (might) remember.

To express a doubt or supposition

The subjunctive is sometimes used after other conjunctions to express doubt or supposition, although this usage is nowadays more often replaced by the indicative.

* I will not let thee go, except [=unless] thou bless me. (Genesis 32:26)

* Murder, though it have no tongue, will speak.

* Whoever he be, he shall not go unpunished.

* But [=although] he were dead, yet shall he live. (New Testament)

Incorrect Hyperusage

The subjunctive has sometimes been used simply as a conditioned variant that follows "if" and similar words even in the absence of a hypothetical situation.

* Johnny asked me if I were afraid. (Barbara in Night of the Living Dead (1968))

In the example quoted, "if" is a substitute for the unambiguous word "whether" ("Johnny asked me whether I was afraid"), and lacks the usual, "in the event that" meaning that it has in other usage such as "If we go to bed now, we'll be up at three o'clock".

Demise of the subjunctive

In many dialects of English, the indicative can take the place of the subjunctive, although this is considered erroneous in formal speech and writing. The similarity of the subjunctive and the past tense has led to the confusion between the two, and the error is evident in various pop culture references and music lyrics.

* If I was President...

* If he was a ghost...

* If I was a rich girl...

However, in the context of the examples above, inversion cannot occur with the indicative as it would with the subjunctive; the following are ungrammatical, except insofar as they could be misinterpreted as questions:

* Was I the President...

* Was he a ghost...

Furthermore, many of the fossil phrases are often re-analyzed as imperative forms rather than as the subjunctive.

According to the Random House College Dictionary, "Although the subjunctive seems to be disappearing from the speech of many, its use is still the mark of the educated speaker."

The subjunctive is not uniform in all varieties of spoken English. However it is preserved in speech, at least in North American English and in many dialects of British English. While use of the subjunctive in natural, informal speech is almost universal among educated speakers, its use is becoming very infrequent among large portions of the population. Some dialects replace it with the indicative or construct it using a modal verb (except perhaps in the most formal literary discourse).

Through the years, some have advocated the formal extinguishment of the subjunctive. W. Somerset Maugham said, "The subjunctive mood is in its death throes, and the best thing to do is to put it out of its misery as soon as possible."

Germanic languages

In the Germanic languages, subjunctives are also usually formed from old optatives. In German, subjunctives are typically marked with an -e ending, and often with i-umlaut, showing once more the presence of the *-i- suffix that is the mark of the old optative. In Old Norse, an -i typically marks the subjunctive; grefr, "he digs", becomes grafi, "let him dig". While most of the signs of this suffix have been removed in Modern English, the change from was to were in the modern English subjunctive of to be also marks addition of a vowel sound to the subjunctive form, and as such represents an echo of the Indo-European optative marker of five thousand years ago.

The subjunctive in German

In German it is generally accepted that there are two forms of the subjunctive mood - Konjunktiv I ('present' subjunctive, often abbreviated as KI) and Konjunktiv II ('past' subjunctive, often abbreviated as KII), both of which can actually be expressed in (almost) all tenses.

The KI is normally used to express indirect (reported) speech. For example:

Er sagte mir, er sei nicht bereit. — He told me that he wasn't ready. In this case, present subjunctive 'sei' replaces the present indicative 'ist'.

This carries a neutral to slightly disclaimerish meaning: the claim reported may be (to the reporter using Konjunktiv) true or not, or unknown. If the speaker doubts the statement, Konjunktiv II may be used, however the usage of Konjunktiv forms does not always follow the principles strictly (Konjunktiv II may replace Konjunktiv I; Konjunktiv I sounds rather formal).

Es wurde gesagt, er habe keine Zeit für so (et)was. — It is said that he has no time for this kind of thing. In this case, present subjunctive 'habe' replaces the present indicative 'hat'.

Many examples of the subjunctive can be found in German newspapers and magazines.

The KI for regular verbs in German is formed by adding -e, -est, -e, -en, -et, -en to the stem. The verb sein (to be) deviates somewhat from this rule, producing ich sei; du sei(e)st; er sei; wir seien; ihr sei(e)t; sie seien. While the use of Konjunktiv I for reported speech is considered "correct" German, its use in colloquial speech is in continual decline.

It is possible to express the KI in various tenses, including the perfect (er sei da gewesen) and the future (er werde da sein) although the latter is rarely used. The Konjunktiv I in the preterite and conditional does exist, but they are identical to their indicative equivalents and are not worth considering in day-to-day communication.

The KII is used to form the conditional tense and, on occasion, as a replacement for the Konjunktiv I when both indicative and subjunctive moods of a particular verb are indistinguishable. Although every verb in the German language can be expressed in the Konjunktiv II, only a small number are actually used in this mood in colloquial speech, such as sein (ich wäre).

The simplest method of forming the conditional in spoken German is to render the verb werden (to become) in the Konjunktiv II form (würde) and append the infinitive of the action, as in An deiner Stelle würde ich das nicht tun (I wouldn't do that if I were you). This analytic method is opposed to the synthetic method: An deiner Stelle täte ich das nicht, which in the day-to-day communication is tendencially less frequent.

In written German, however, the synthetic form (ich täte) is seen by many dictionaries as the only proper form for the term, while the analytical form (ich würde tun) is a substitute that should be avoided as far as possible. Only the synthetic form is regarded as the language better, if you speak German upscale.

The KII is formed from the stem of the preterite (imperfect) form of the verb and appending the appropriate Konjunktiv I ending as appropriate, although in most regular verbs the final 'e' in the stem is dropped. In most cases, an umlaut is appended to the stem vowel if possible (i.e. if it is a, o, u or au), for example: ich war → ich wäre, ich brachte → ich brächte.

The subjunctive in Dutch

Dutch has the same subjunctive tenses as German (described above), but nowadays they are almost never used. The same two tenses as in German are sometimes considered subjunctive and sometimes conditional.

Some sentences that are used often in Dutch still contain the subjunctive mood:

Leve de koningin! (Long live the Queen!)
Men neme (One takes (found in recipes))
Uw naam worde geheiligd (Hallowed be your name (Lord's Prayer))
Zo waarlijk helpe mij God almachtig (So help me God (when swearing an oath))
Het zij zo (So be it)
God zegene u (God bless you)
De HERE zegene u en behoede u; de HERE doe Zijn aangezicht over u lichten en zij u genadig; de HERE verheffe Zijn aangezicht over u en geve u vrede (May the LORD bless you, and keep you; May the LORD make his face shine to upon you, and be gracious to you; May the LORD turn his countenance to you and grant you peace (Priestly Blessing))

The above sentences are all in the present tense, the past tense subjunctive mood of zijn (to be) is also used rather frequently to indicate a non-reality, something that didn't happen. It translates with the English past subjunctive were:

Hij ware gekomen, als u hem geen pijn had gedaan (He would have come, if you hadn't hurt him)
De graaf sprak over de diefstal van honderd goudstukken als ware het een kleinigheid (The count spoke about the theft of a hundred gold coins as if it were a small thing)

Latin and the Romance languages

The Latin subjunctive is mostly made of optative forms, while some of the original subjunctive forms went to make the Latin future tense, especially in the Latin third conjugation. In Latin, the *-i- of the old optative manifests itself in the fact that the Latin subjunctives typically have a high vowel even when the indicative mood has a lower vowel; Latin rogamus, "we ask", makes a subjunctive rogemus, "let us ask."

The subjunctive mood retains a highly distinct form for nearly all verbs in Portuguese, Spanish and Italian (among other Latin languages), and for a number of verbs in French. All of these languages inherit their subjunctive from Latin, where the subjunctive mood combines both forms and usages from a number of original Indo-European inflection sets (described above), including the original subjunctive and the optative mood.

In many cases, the Romance languages use the subjunctive in the same ways that English does; however, they use them in other ways as well. For example, English generally uses the auxiliary may or let to form desiderative expressions, such as "Let it snow." The Romance languages use the subjunctive for these; French, for example, would say, "Qu'il neige" and "Qu'ils vivent jusqu'à leur vieillesse." (However, in the case of the first-person plural, these languages have imperative forms: "Let's go" in French is "Allons-y.") Also, the Romance languages tend to use the subjunctive in various kinds of subordinate clauses, such as those introduced by words meaning although (English: "Although I'm old, I feel young"; French: Bien que je sois vieux, je me sens jeune.) In Spanish, phrases with words like lo que (that which, what), quien (who), or donde (where) and subjunctive verb forms are often translated to English with some variation of "whatever". (Spanish: "lo que sea", English: "whatever", "anything"; Spanish: "donde sea", English: "wherever"; Spanish: "quien sea", English: "whoever"; Spanish: "lo que quieras", English: "whatever you want"; Spanish: "cueste lo que cueste", English: "whatever it costs")

The subjunctive in French

In French, despite the deep phonetic changes that the language has undergone from the original Latin, which include the loss of many inflections in the spoken language, the subjunctive (le subjonctif) remains prominent, largely because the subjunctive forms of many common verbs are strongly marked phonetically; compare the indicative je sais (I know) and its subjunctive counterpart je sache. (However, the present indicatives and present subjunctives of most verbs are homonyms when they have singular subjects: je parle [I speak] is both the present indicative and the present subjunctive.)

Use of the subjunctive is in many respects similar to English:

Jussive: Il faut qu'il comprenne ça.: "It is necessary that he understand this."
Desiderative: Vive la reine!: "Long live the queen!"

But sometimes not:

Desiderative: Que la lumière soit !: "Let there be light!"
In certain subordinate clauses:

Bien que ce soit mon anniversaire... "Even though it is my birthday..."

(Note that, in correct English, the phrase above should read "Even though it be..." since the verb is conjugated in the present subjunctive; however, such usage is uncommon.)

Avant que je ne m'en aille... "Before I go away..."

French also has an imperfect subjunctive, which in older, formal, or literary writing replaces the present subjunctive in a subordinate clause when the main clause is in a past tense:

English: It was necessary that he speak (present subjunctive).
Everyday modern French: Il était nécessaire qu'il parle (present subjunctive).
Older, formal, or literary French: Il était nécessaire qu'il parlât (imperfect subjunctive).

Also in older, formal, or literary writing, the imperfect and pluperfect subjunctives double as a "second form" of the conditional and conditional perfect, in which case they are used in both the protasis and the apodosis:

English: Had we known (pluperfect subjunctive), we could have prevented (conditional perfect) it.
Everyday modern French: Si on l'avait su (pluperfect indicative), on aurait pu (conditional perfect) l'empêcher.
Older, formal, or literary French: L'eussions-nous su (conditional perfect, second form), nous l'eussions pu (conditional perfect, second form) empêcher.

For more on the subjunctive in French, see French verbs.

The subjunctive in Italian

The Italian subjunctive (il congiuntivo) is similar to the French subjunctive in formation and use, but is somewhat more common.

The subjunctive is used mainly in subordinate clauses following a set phrase or conjunction, such as benché, senza che, prima che, or purché for example. It is also used with verbs of doubt, possibility and expressing an opinion or desire, for example with credo che, è possibile che, and ritengo che, and with superlatives and virtual superlatives.

English: The most beautiful girl I know.
Italian: La ragazza più bella che io conosca.

One difference between the French subjunctive and the Italian is that Italian uses the subjunctive after expressions like "Penso che" ("I think that"), where French would use the indicative.

Present subjunctive

The present subjunctive is similar to, but still mostly distinguishable from, the present indicative. Subject pronouns are often used with the present subjunctive where they are normally omitted in the indicative, since in the 1st, 2nd and 3rd person singular forms are spelt the same, so the person is not implicitly implied from the verb. Irregular verbs tend to follow the 1st person singular form, such as the present subjunctive forms of andare, which goes to vada etc (1st person sing form is vado).

The present subjunctive is used in a range of situations in clauses taking the subjunctive.

English: “It’s possible that they may have to leave.”
Italian: “È possibile che debbano partire”

English: “My parents want me to play the piano.”
Italian: “I miei genitori vogliono che io suoni il pianoforte”

The present subjunctive is used mostly in subordinate clauses, as in the examples above. However, exceptions include imperatives using the subjunctive (using the 3rd person), and general statements of desire.

English: “Be careful!”
Italian: “Stia attento!”

English: “Long live the republic!”
Italian: “Viva la repubblica!”

Imperfect subjunctive

The Italian imperfect subjunctive is very similar in appearance to the French imperfect subjunctive, and forms are largely regular, apart the verbs essere, dare and stare (which go to fossi, dessi and stessi etc). However, unlike in French, where it is often replaced for the present subjunctive, the imperfect subjunctive is far more common. Verbs with a contracted infinitive, such as dire (short for dicere) revert to the longer form in the imperfect subjunctive (to give dicessi etc, for example).

The imperfect subjunctive is used in subordinate clauses taking the subjunctive where the sense of the verb requires the imperfect tense.

English: “It seemed that Elsa wasn’t coming.”
Italian: “Sembrava che Elsa non venisse.”

English: “The teacher slowed down, in order that we understand everything.”
Italian: “L’insegnante rallentava, affinché capissimo tutti.”

The imperfect subjunctive is used in “if” clauses, where the main clause is in the conditional tense, as in English and German.

English: “If I had a lot of money, I would buy many cars.”
Italian: “Se avessi molti soldi, comprerei tante macchine.”

English: “You would know if we were lying.”
Italian: “Sapresti se mentissimo.”

Perfect and pluperfect subjunctives

The perfect and pluperfect subjunctives are formed much like the indicative perfect and pluperfect, except the auxiliary (either avere or essere) verb takes the present and imperfect subjunctive respectively.

They are used in subordinate clauses which require the subjunctive, where the sense of the verb requires use of the perfect or pluperfect.

English: “Although they didn’t kill the doctor, the police arrested the men.”
Italian: “Benché non avessero ucciso il medico, la polizia ha arrestato gli uomini.”

English: “I would have done it, provided you had helped me!”
Italian: “Lo avrei fatto, purché tu mi avessi assistito.”

The subjunctive in Spanish

In Spanish, the subjunctive (subjuntivo) is used in conjunction with impersonal expressions, expressions of emotion, opinion, or viewpoint. It is also used to describe situations that are considered unlikely or are in doubt, as well as for expressing disagreement, volition, or denial.

There are many common expressions that commonly introduce subjunctive clauses. Examples include:

Es una pena que... "It's a shame that..."
Quiero que... "I want..."
Ojalá que... "Hopefully..."
Es importante que... "It's important that..."
Me alegro de que... "I'm happy that..."
Es bueno que... "It's good that..."
Es necesario que... "It's necessary that..."
Dudo que... "I doubt that..."

Spanish has two past subjunctive forms. They are almost identical, except that where the "first form" has -ra-, the "second form" has -se-. Both forms are usually interchangeable although the -se- form may be more common in Spain than in other Spanish-speaking areas. The -ra- forms may also be used as an alternative to the conditional in certain structures.

The present subjunctive

When do you use subjunctive?

When there are two clauses, seperated by que. However, not all que clauses require subjunctive. They must also have at least one of the following criteria.
As the fourth edition of Mosaicos states, when "the verb of the main clause expresses emotion (e.g. fear, happiness, sorrow)"
Impersonal expressions are used in the main clause (It's important that...)
Always remember that the verb in the second clause is the one that is in subjunctive!

How to form:

Go to the present tense yo form. (ex. hablar --> hablo)
Drop the o (hablo --> habl)
Add the opposite ending (habl --> hable, hables, hable, hablemos, habléis, hablen)
Here are the endings for AR and ER/IR verbs:

e emos
es éis
e en

ER/IR

a amos
as áis
a an

HOWEVER, as we all know, there are many irregular verbs in the Spanish language and the subjunctive tense is no exception. The following are the irregular verbs in subjunctive and their conjugations:

Ser

sea seamos
seas seáis
sea sean

Estar

esté estemos
estés estéis
esté estén

vaya vayamos
vayas vayáis
vaya vayan

Saber

sepa sepamos
sepas sepáis
sepa sepan

Dar

dé demos
des deis
dé den

ALSO, one must remember the ever so lovely, CAR/GAR/ZAR verbs. For example:

Jugar

juegue juguemos
juegues juguéis
juegue jueguen

Tocar

toque toquemos
toques toquéis
toque toquen

Cruzar

cruce crucemos
cruces crucéis
cruce crucen

Examples:

Ojalá me compren (comprar) un regalo. (Hopefully, they will buy me a gift.)
Te recomiendo que no corras (correr) con tijeras. (I recommend that you don't run with scissors.)
Dudo que el restaurante abra (abrir) a las seis. (I doubt that the restaurant opens at six.)
Lo discutiremos cuando venga (venir). (We'll talk about it when he/she comes.)
Es importante que nosotros hagamos ejercicio. (It's important that we excercise.)
Me alegro de que tu seas mi amiga. (I'm happy that you are my friend.)

The past (imperfect) subjunctive

Used interchangeably, the past (imperfect) subjunctive can either end in "-se" or "-ra". Both forms stem from the third person plural (ellos, ellas, ustedes) of the preterite tense. For example, with the verb "estar", when conjugated in the third person plural of the preterite tense, it becomes "estuvieron". Then, you drop the "-ron" ending, and add either "-se" or "-ra". Thus, it becomes "estuviese" or "estuviera". The past subjunctive may be used with "if... then" statements with the conditional tense.

Example:

Si yo fuera el maestro, no daría demasiada tarea. (If I were the teacher, I wouldn't give too much homework.)

Spanish used to have a future subjunctive tense, but it is now all but extinct. It is never heard in everyday speech, and is usually reserved for literature, archaic phrases and expressions, and legal documents. Phrases expressing the subjunctive in a future time-frame instead employ the present subjunctive. For example: "I hope it will rain tomorrow" would simply be "Espero que llueva mañana" (where llueva is the third-person singular present subjunctive of llover, "to rain").

The subjunctive in Portuguese

In Portuguese, the subjunctive (subjuntivo or conjuntivo) is used to talk about situations which are seen as doubtful, imaginary, hypothetical, demanded, or required. It can also express emotion, opinion, disagreement, denial, or a wish. Its value is similar to the one it has in formal English:

Command: Faça-se luz! "Let there be light!"
Wish: Viva o rei! "Long live the king!"
Necessity: É importante que ele compreenda isso. "It is important that he understand that."
In certain subordinate clauses:

Ainda que seja meu aniversário... "Even though it be my birthday..."
Antes que eu vá... "Before I go..."

As in Spanish, the imperfect subjunctive is in vernacular use, and it is employed, among other things, to make the tense of a subordinate clause agree with the tense of the main clause:

English: It is [present indicative] necessary that he speak [present subjunctive]. → It was [past indicative] necessary that he speak [present subjunctive].
Portuguese: É [present indicative] necessário que ele fale [present subjunctive]. → Era necessário [past (imperfect) indicative] que ele falasse [past (imperfect) subjunctive].

The imperfect subjunctive is also used when the main clause is in the conditional:

English: It would be [conditional] necessary that he speak [present subjunctive].
Portuguese: Seria [conditional] necessário que ele falasse [imperfect subjunctive].

Note that there are authors who regard the conditional of Portuguese as a 'future in the past' of the indicative mood, rather than as a separate mood; they call it futuro do pretérito ("future of the past"), especially in Brazil.

Portuguese differs from other Romance languages in having retained the medieval future subjunctive (futuro do subjuntivo), which is rarely used in Spanish and Galician and has been lost in other West Iberian Romance languages. It expresses a condition that must be fulfilled in the future, or is assumed to be fulfilled, before an event can happen. Spanish and English will use the present tense in this type of clause.

For example, in conditional sentences whose main clause is in the conditional, Portuguese, Spanish and English employ the past tense in the subordinate clause. But if the main clause is in the future, Portuguese will employ the future subjunctive where English and Spanish use the present indicative. Contrast the following two sentences.

English: If I were [past subjunctive] king, I would end [conditional] hunger.

Spanish: Si fuera [imperfect subjunctive] rey, acabaría con [conditional] el hambre.
Portuguese: Se fosse [imperfect subjunctive] rei, acabaria com [conditional] a fome.

English: If I am [present indicative] elected president, I will change [future indicative] the law.

Spanish: Si soy [present indicative] elegido presidente, cambiaré [future indicative] la ley.
Portuguese: Se for [future subjunctive] eleito presidente, mudarei [future indicative] a lei.

The first situation is counterfactual; we know that the speaker is not a king. But the second statement expresses a promise about the future; the speaker may yet be elected president.

For a different example, a father speaking to his son might say:

English: When you are [present indicative] older, you will understand [future indicative].
Spanish: Cuando seas [present subjunctive] mayor, comprenderás [future indicative].
French: Quand tu seras [future indicative] grand, tu comprendras [future indicative].
Portuguese: Quando fores [future subjunctive] mais velho, compreenderás [future indicative].''

The future subjunctive is identical in form to the personal infinitive in regular verbs, but they differ in some irregular verbs of frequent use. However, the possible differences between the two tenses are due only to stem changes. They always have the same endings.

The subjunctive in Romanian

Romanian is part of the Balkan Sprachbund and as such uses the subjunctive (conjunctivul) much more extensively than other Romance languages. The subjunctive forms always include the conjunction să, which within these verbal forms plays the role of a morphological structural element. The subjunctive has two tenses: the past tense and the present tense.

Present tense

The present subjunctive of the regular verbs is formed by adding specific endings to the stem of the infinitive (e.g. El vrea să cânte, he wants to sing). The actual verbal form is preceded by the conjunction să. The present tense is by far the most widely used of the two subjunctive tenses and is used frequently after verbs that express wish, preference, permission, possibility, request, advice, etc.: a vrea to want, a dori to wish, a prefera to prefer, a lăsa to let, to allow, a ruga to ask, a sfătui to advise, a sugera to suggest, a recomanda to recommend, a cere to demand, to ask for, a interzice to forbid, a permite to allow, to give permission, a se teme to be afraid, etc.

When used independently, the subjunctive indicates a desire, a fear, an order or a request, i.e. has modal and imperative values. The present subjunctive is used in questions having the modal value of should:

Să plec? Should I leave?
Să mai stau? Should I stay longer?
De ce să plece? Why should he/she leave?

The present subjunctive is often used as an imperative, mainly for other persons than the 2nd person. When used with the 2nd person, it is even stronger than the imperative. The 1st person plural can be preceded by the interjection hai, which intensifies the imperative meaning of the structure:

Să mergem! / Hai să mergem! Let's go!
Să plece imediat! I want him to leave immediately!
Să-mi aduci un pahar de apă! Bring me a glass of water!

The subjunctive present is used in certain set phrases used as greetings in specific situations:

Să creşti mare! (to a child, after he / she declared his / her age or thanked for something)
Să ne (să-ţi, să vă) fie de bine! (to people who have finished their meals)
Să-l (să o, să le etc.) porţi sănătos / sănătoasă! (when somebody shows up in new clothes, with new shoes)
Dumnezeu să-l (s-o, să-i, să le) ierte! (after mentioning the name of a person who died recently)

Past tense

The past tense of the subjunctive mood has one form for all persons and numbers of all the verbs, which is să fi followed by the past participle of the verb. The past subjunctive is used after the past optative-conditional of the verbs that require the subjunctive (a trebui, a vrea, a putea, a fi bine, a fi necesar, etc.), in constructions that express the necessity, the desire in the past:

Ar fi trebuit să fi rămas acasă. You should have stayed home.
Ar fi fost mai bine să mai fi stat. It would have been better if we had stayed longer.

When used independently, the past subjunctive indicates a regret related to a past accomplished action that is seen as undesirable at the moment of speaking:

Să fi rămas acasă… We should have stayed home. (Note: the same construction can be used for all persons and numbers)

The subjunctive in Semitic Languages

The subjunctive in Arabic

In Standard/Literary Arabic the verb in its imperfective aspect (al-muḍāri‘) has a subjunctive form called the manṣūb form. It is distinct from the imperfect indicative in most of its forms: where the indicative has "u", the subjunctive has "a"; and where the indicative has "na", the subjunctive has nothing at all (except in the 3rd plural feminine where the "na" of the indicative is retained).

Indicative 3 sing. masc. yaktubu "he writes / is writing / will write" → Subjunctive yaktuba "he may / should write"
Indicative 3 plur. masc. yaktubūna "they write" → Subjunctive yaktubū "they may write"
Indicative 3 plur. fem. yaktubna "they write" → Subjunctive yaktubna "they may write"

The subjunctive is used in that-clauses, after Arabic an: urīdu an aktuba "I want to write". However in conditional and precative sentences, such as "if he goes" or "let him go", a different form of the imperfective aspect, the jussive, majzūm, is used.

In many spoken Arabic dialects there remains a distinction between indicative and subjunctive, but there it is not through endings but a prefix. In Levantine Arabic, the indicative has b- while the subjunctive lacks it:

3 sing. masc. huwwe byuktob "he writes / is writing / will write" → yuktob "he may / should write"
3 plur. masc. homme byukotbu → yukotbu

Egyptian Arabic has a similar prefix bi-, while Moroccan Arabic uses ka- or ta-.

The subjunctive in Hebrew

Final vowels disappeared from Hebrew in prehistoric times, so the distinction between indicative, subjunctive and jussive is nearly totally blurred even in Biblical Hebrew. A few relics remain for roots with a medial or final semivowel, such as yaqūm "he rises / will rise" versus yaqom "may he rise" and yihye "he will be" versus yehi "let him be". In modern Hebrew the situation has been carried even further, with the falling into disuse of forms like yaqom and yehi; instead, the future tense (prefix conjugation) is used for the subjunctive, often with the particle she- added to introduce the clause, if it is not already present (similar to French que).

"שיבוא" (Sheyavo) — "Let him come" or "May he come" (literally, "That-(he)-will-come")
"אני רוצה שיבוא" (Ani rotzeh sheyavo) — "I want him to come" (literally, "I want that-(he)-will-come")

The Biblical subjunctive survives in the third person singular forms of the verbs to be (להיות — lihyot, יהי/תהי or יהא/תהא) and to live (לחיות — likhyot, יחי/תחי), mostly in a literary register:

"יחי המלך" (Y'khi ha-melekh) — "Long live the king" (literally, "Live the-king")

The subjunctive in Hungarian

This mood in Hungarian is generally used to express polite demands and suggestions. The endings are identical between imperative, conjunctive and subjunctive; it's therefore often called the conjunctive-imperative mood.

Examples:

Add nekem! Give it to me. Demand.
Menjünk! let's go. Suggestion.
Menjek? shall I go? Suggestion/question.
Menj! go! Demand.

Note that "demand" is no where near as rude as it might come across in English. It's a polite but firm request, but not as polite as, say, "would you...".

The characteristic letter in its ending is -j-, and in the definite conjunctive conjugation the endings appear very similar to those of singular possession, with a leading letter -j-.

An unusual feature of the mood's endings is that there exist a short and a long form for the second person singular (i.e. "you"). The formation of this for regular verbs differs between the indefinite and definite: the indefinite requires just the addition of -j, which differs from the longer ending in that the last two letters are omitted (-j and not -jel for example in menj above). The definite also drops two letters, but a different two. It drops, for example - the -ja- in -jad, leaving just -d, as can be seen in add above.

There are several groups of exceptions involving verbs that end in -t. The rules for how this letter, and a preceding letter, should change when the subjunctive endings are applied are quite complicated. As usual, gemination of a final sibilant consonant is demonstrated when a j-initial ending is applied:

mos + -jak gives mossak let me wash (-j- changes to -s-)

When making references to the demands of others, the subjunctive is demonstrated:

kérte, hogy menjek. He asked that I go. (he asked me to go) Here, "I go" is in the subjunctive.

Notes

Bibliography

Curme, George O. (1977). "A Grammar of the English Language". Verbatim. ISBN 0-930454-01-4 (reprint of 1931 edition from D. C. Heath and Company)
Chalker, Sylvia (1995). "Dictionary of English Grammar". Oxford University Press. ISBN 0-19-860055-0
Fowler, H. W. (1926). "A Dictionary of Modern English Usage". Oxford University Press.
Hardie, Ronald G. (1990). "English Grammar". Harper Collins. ISBN 0-00-458349-3
Nesfield, J. C. (1939). "Manual of English Grammar and Composition". Macmillan.