The regular Spanish verbs that end in -ar, -er, and -ir take a pretty regular method in forming simple tenses. You start with the stem of the word and add an ending according to the person or pronoun you use. The following tables show how to change tenses for -ar verbs (hablar, to speak is the example) and -er and -ir verbs, in which comer, to eat, and vivir, to live, are the examples.
| Tense | Stem | yo | tú | él, ella, usted | nosotros/as | vosotros/as | ellos/as, ustedes |
|---|---|---|---|---|---|---|---|
| Present | habl + | -o | -as | -a | -amos | -áis | -an |
| Imperfect | habl + | -aba | -abas | -aba | -ábamos | -abais | -aban |
| Preterit | habl + | -é | -aste | -ó | -amos | -asteis | -aron |
| Future | hablar + | -é | -ás | -á | -emos | -éis | -án |
| Conditional | hablar + | -ía | -ías | -ía | -íamos | -íais | -ían |
| Present Subjunctive | habl + | -e | -es | -e | -emos | -éis | -en |
| Imperfect Subjunctive | habl + | -ara | -aras | -ara | -áramos | -arais | -aran |
| Imperfect Subjunctive (alternative) | habl + | -ase | -ases | -ase | -ásemos | -aseis | -asen |
The first imperfect subjunctive form is the one most commonly used, not the alternative.
| Tense | Stem | yo | tú | él, ella, usted | nosotros/as | vosotros/as | ellos/as, ustedes |
|---|---|---|---|---|---|---|---|
| Present | com/viv + | -o | -es | -e/-a | -emos/-imos | -éis/-ís | -en |
| Imperfect | com/viv + | -ía | -ías | -ía | -íamos | -íais | -ían |
| Preterit | com/viv + | -í | -iste | -ió | -imos | -isteis | -ieron |
| Future | comer/vivir + | -é | -ás | -á | -emos | -éis | -án |
| Conditional | comer/vivir + | -ía | -ías | -ía | -íamos | -íais | -ían |
| Present Subjunctive | com/viv + | -a | -as | -a | -amos | -áis | -an |
| Imperfect Subjunctive | com/viv + | -iera | -ieras | iera | -iéramos | -ierais | -ieran |
| Imperfect Subjunctive (alternative) | com/viv + | -iese | -ieses | -iese | -iésemos | -ieseis | -iesen |