To conjugate a regular verb in the preterite tense, remove the infinitive ending and add the appropriate endings. For an – ar verb that is regular in the preterite, use the endings from Table 1. (Not all verbs that were regular in the present tense are regular in the preterite.)
Regular Verbs in the Preterite Tense
The endings are a little confusing because the él, ella, and usted forms end in – ó in the preterite tense, but the yo form ends in – o (no accent) in the present tense. Take note of the accent mark on the preterite forms because that is the only difference. The yo form of all regular preterite verbs always has an accent mark as well. Remember to pronounce these words with the stress on the last syllable. The tú form is also different in the preterite tense: it never ends in –s like it does in the present tense.
Regular – ar verbs have the same nosotros form in the preterite as they do in the present tense. The only way you will know whether an – ar verb in the nosotros form is in the preterite or present tense is the context of the sentence. If you see one of these words in the sentence, you will know the verb is conjugated in the preterite tense.
Hablar (to speak) is a regular verb in the preterite, so it will serve as a good example. Table 2 is a conjugation chart for the verb hablar in the preterite tense. Since the preterite is a past tense, these forms translate to the English past tense form “spoke.”
Table 3 shows that the endings for – er verbs and – ir verbs are the same for regular verbs in the preterite tense.
Notice that the nosotros/nosotras form of an – ir verb looks identical in both the present and preterite tenses, but an – er verb has a different nosotros form in the preterite. The nosotros/nosotras form in the present tense is the only form where – er and – ir verbs are different.
The verb comer (to eat) is a regular – er verb in the preterite. Table 4, which shows the English past tense form of ate, is a good example of regular – er verb forms in the preterite tense.
The verb escribir (to write) is a regular – ir verb in the preterite. Table 5, which shows the English past tense form of wrote, is a good example of regular – ir verb forms in the preterite tense.