Three common suffixes are -dom, which is a place or state of being, -ism, which is a belief and -ment, which is a condition of the subject. So freedom is the state of being free, communism is a belief set and development, the condition of an area as being developed. All of these are common to English nouns, with other types of words receiving their own common suffixes and interchanging depending on the context.
Verbs have far less common suffixes, generally using -ate, -en, -ify and -ize. All of these verbs modify the word so that something becomes something else, such as in vilify, turning someone into a villain or liquify, to turn an object to a liquid.
Adjectives include -able, -al, -esque, -ful and -ical, and so on. These alter the characteristics of the adjective itself, modifying how the adjective describes its subject. For instance, a green leaf would just be green, but the greenest leaf is more green than others. Greenest is an adjective modified with a suffix.
Many suffixes change according to the word they are modifying. The word drinkable and the word flexible differ in that the suffix is the same but altered by the content of the base word.