Some examples of simple past tense verbs are: ate, ran, swam, wrote, sat, slept, danced, read, drove and saw. Each of them refers to an activity that was performed at some time in the past and is not continuing in the present.
Most simple past tense verbs end with the suffix -ed. Examples of this include walked, talked, looked, greeted, veered, tilted, wobbled and barked. However, some simple past tense verbs do not share this ending. These verbs are termed "irregular verbs" and include words such as felt, put, arose, became, caught, chose, fought, heard and many others. There are no rules for the construction of the simple past tense form of irregular verbs. English speakers either consciously or unconsciously memorize them in the proper context while learning the language.
Regular verbs can present spelling difficulties. While they suffix -ed is added, some double their final letter. For instance, the word stop becomes stopped in simple past tense. This generally happens in cases where the word contains a consonant, a vowel and another consonant. However, there are exceptions; the final letter is not doubled if it is a w, x or y. In longer words, such as preferred, the last letter is doubled if the final syllable ends in a consonant, a vowel, and another consonant and that syllable is stressed. It is not doubled if the first syllable is stressed, such as entered. If the verb ends in e already, only a d is added. If the verb ends in a y it is changed to an i and then ed is added.