Going from the Present Tense to the Preterite.

Going from the Present Tense to the Preterite.

First: Remember how verbs work in general:
Hablar = to talk. This is an infinitive (dictionary form of the verb).

Second: Take away the ending (-ar) and you have your stem, or root, of the verb. In this case: Habl = talk

Third: Remember each subject of the verb, takes a different ending. What are the subjects?
Yo, Tú, usted (Ud.), él, ella,
Nosotros/as, Vosotros/as, usteded (Uds.), ellos and ellas.

Fourth: To make the verb "agree" with who is doing the action, you need to "match" the ending for the "verb family" (-ar, -er, -ir) with the subject of the verb (see the third step).

Fifth: The present tense says the person does, or is doing the acting at this time (presently), or is going to do the action soon. The verb endings in the PRESENT TENSE (what we've used until we started the Preterite)
The verb endings in the PRESENTE/PRESENT TENSE are:
Yo -o
Tú -as, or -es
Ud./él/ella -a, or -e
Nosotros/as -amos, -emos, or imos
Vosotros/as -áis, éis, or ís
Uds./ellos/ellas -an, -en

Sixth: The preterite tense says the person did the action in the past. That is why the time expressions associated with these verbs are ones like: Yesterday, Last night, Last week, Last summer, 2 years ago, etc.
The verb endings in PRETERITO/preterite are:
Yo -é, or í
Tú -aste, or -iste
Ud./él/ella -ó, or -ió
Nosotros/as -amos, or imos
Vosotros/as -asteis, or -isteis
Uds./ellos/ellas -aron, -ieron

NOW PUT IT ALL TOGETHER:

Yesterday I learned the preterite:
(1) Which verb? = Aprender: to learn
(2) Take away the -er and replace it with the yo ending for -er verbs in the preterite (because it happened yesterday = past)
(3) Translate the rest of the sentence:
Ayer (yo) aprendí el pretérito