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Read the verb blueprint · A0

Infinitives and verb families

Recognize an infinitive and sort regular verbs into the -ar, -er, and -ir families.

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Patterninfinitive stem + -ar, -er, or -ir

See it in context

hablar → habl- + -arto speakAn -ar infinitive
comer → com- + -erto eatAn -er infinitive
vivir → viv- + -irto liveAn -ir infinitive

How it works

An infinitive names an action without saying who does it. English infinitives often use “to,” as in “to speak.” Spanish infinitives end in -ar, -er, or -ir: hablar, comer, vivir.

The letters before the final -ar, -er, or -ir are the stem. For hablar, habl- is the stem and -ar is the infinitive ending. Conjugation replaces that infinitive ending with an ending that matches the subject.

Keep the three families visible. Their endings overlap, but the differences carry useful information.

You will use this to

Practice loop

  1. Notice the patternChoose the infinitive—the unchanged dictionary form.
    5 questions
  2. Choose the formIdentify the family from the infinitive ending.
    5 questions
Mastery target80% across 10 attempts