Basarse Present Tense Conjugation in Spanish

The present tense of basarse — “to be based on” in English — is the form you need for what happens now, for habits and for general truths. This page gives you the full present conjugation table for basarse with all six persons, explains exactly how the tense is formed for this verb, shows when to use it with real examples, and finishes with a quiz so you can test yourself. Basarse means to be based on, and it is the reflexive partner of basar: a theory is based on experience, a decision is based on the facts, a film is based on a true story. It takes en for the foundation, as in basarse en hechos reales. Basarse is a reflexive regular -ar verb, so the notes below explain exactly where it follows the rules and where it breaks them. To see it in a real sentence: Me baso en los datos del informe.

Present tense conjugation table: basarse

Every person of basarse in the present tense, with the reflexive pronoun. The gerund is basándose with the pronoun attached, and the past participle is basado.

Present indicative

Person Form
yo me baso
tú te basas
él/ella/Ud. se basa
nosotros/as nos basamos
vosotros/as os basáis
ellos/ellas/Uds. se basan

How the present of basarse is formed

The present of basarse is built from the stem bas- plus the present endings for -ar verbs. Take the infinitive, drop the -ar ending and the reflexive -se, and add the ending that matches the person. The table below shows the endings, and the full table above shows them attached to the stem.

Person Ending Form
yo -o me baso
tú -as te basas
él/ella/Ud. -a se basa
nosotros/as -amos nos basamos
vosotros/as -áis os basáis
ellos/ellas/Uds. -an se basan

For basarse there are no surprises in the present: every form is the stem bas- plus the regular ending, so once you know the endings you know the whole tense.

Because basarse is reflexive, the pronoun goes before the verb in every form: me, te, se, nos, os, se. In the gerund the pronoun attaches to the end: basándose.

When to use the present tense with basarse

Habits and routines

Use the present for things you do regularly.

Yo me baso en los datos del informe. — I rely on on the data in the report.

General facts

Use the present for facts and general truths that do not change.

Él/Ella se basa en la experiencia de años. — He relies on on years of experience.

What is happening right now

Use the present for what is happening at this moment.

Ahora, Nosotros/as nos basamos en lo que dice el médico. — Right now, We rely on on what the doctor says.

Near-future plans

Use the present for fixed plans in the near future, especially with mañana or la semana que viene.

Mañana, Tú te basas en hechos reales. — Tomorrow, You rely on on real facts.

Instructions and timeless statements

Use the present for instructions, rules and statements that are always true.

Él/Ella se basa en los datos del informe. — He relies on on the data in the report.

The present vs the preterite

The present and the preterite answer different questions: the present says what happens regularly or right now, while the preterite says what happened once and finished. Compare the same idea in both tenses with basarse.

  1. Yo me baso en los datos del informe. — I rely on on the data in the report. / Ayer, Yo me basé en los datos del informe. — Yesterday, I relied on on the data in the report.
  2. Yo me baso en la experiencia de años. — I rely on on years of experience. / Ayer, Yo me basé en la experiencia de años. — Yesterday, I relied on on years of experience.
  3. Yo me baso en lo que dice el médico. — I rely on on what the doctor says. / Ayer, Yo me basé en lo que dice el médico. — Yesterday, I relied on on what the doctor says.

Example sentences in the present tense

Seven sentences with basarse in the present tense only, covering all six persons.

  1. Yo me baso en los datos del informe. — I rely on on the data in the report.
  2. Tú te basas en la experiencia de años. — You rely on on years of experience.
  3. Él/Ella se basa en lo que dice el médico. — He relies on on what the doctor says.
  4. Nosotros/as nos basamos en hechos reales. — We rely on on real facts.
  5. Vosotros/as os basáis en los datos del informe. — You rely on on the data in the report.
  6. Ellos/as se basan en la experiencia de años. — They rely on on years of experience.
  7. Yo me baso en lo que dice el médico. — I rely on on what the doctor says.

Common mistakes

  1. Wrong: Yo basa en los datos del informe. — Right: Yo baso en los datos del informe. — The person matters: basa is the él/ella/Ud. form, while the yo form is baso.
  2. Wrong: Ayer, yo baso en la experiencia de años. — Right: Ayer, yo basé en la experiencia de años. — With ayer, use the preterite (basé), not the present. The present is for habits and for right now.
  3. Wrong: Yo baso en los datos del informe. — Right: Yo me baso en los datos del informe. — Basarse is reflexive, so the pronoun me is required in the present tense too.
  4. Wrong: Espero que él basa en la experiencia de años. — Right: Espero que él base en la experiencia de años. — After espero que, Spanish needs the subjunctive: base, not the present indicative basa.

Quiz: the present tense of basarse

Eight questions on the present tense of basarse. Choose the right form, then check the answer key below.

  1. Complete the sentence: Yo ___ en los datos del informe. (present tense, yo) A. me baso B. te basas C. se basa D. nos basamos

  2. Complete the sentence: Tú ___ en la experiencia de años. (present tense, tú) A. me baso B. se basa C. nos basamos D. te basas

  3. Complete the sentence: Él/Ella ___ en lo que dice el médico. (present tense, él/ella/Ud.) A. te basas B. nos basamos C. se basa D. me baso

  4. Complete the sentence: Nosotros/as ___ en hechos reales. (present tense, nosotros/as) A. se basa B. nos basamos C. me baso D. te basas

  5. Complete the sentence: Vosotros/as ___ en los datos del informe. (present tense, vosotros/as) A. os basáis B. me baso C. te basas D. se basa

  6. Complete the sentence: Ellos/as ___ en la experiencia de años. (present tense, ellos/ellas/Uds.) A. me baso B. te basas C. se basa D. se basan

  7. Which is the gerund of basarse? A. baso B. basé C. basando D. basado

  8. Which is the past participle of basarse, used with haber in the perfect tenses? A. basé B. basado C. basando D. baso

Answer key

  1. me baso — The yo present form of basarse is me baso.
  2. te basas — The tú present form of basarse is te basas.
  3. se basa — The él/ella/Ud. present form of basarse is se basa.
  4. nos basamos — The nosotros/as present form of basarse is nos basamos.
  5. os basáis — The vosotros/as present form of basarse is os basáis.
  6. se basan — The ellos/ellas/Uds. present form of basarse is se basan.
  7. basando — The gerund of basarse is basando: estoy basando.
  8. basado — The past participle of basarse is basado: he basado, has basado, ha basado.

Frequently asked questions

How is the present tense of basarse formed?

Take the infinitive basarse, drop the -ar ending and the reflexive -se to get the stem bas-, then add the present endings: -o, -as, -a, -amos, -áis, -an. The full table is above, with every person. No, the present of basarse is fully regular: the stem bas- plus the standard -ar endings gives every form.

When do I use the present tense of basarse?

Use the present for habits, facts and what is happening right now. For example: Me baso en los datos del informe.

What is the difference between the present and the preterite of basarse?

The present (baso) and the preterite (basé) answer different questions: the present is for habits and for right now, while the preterite is for one finished action. Compare them in the contrast section above.

How do I practise the present of basarse?

Drill the six forms in the table until you can say them without looking, then use the full conjugation of basarse to see how the present fits with the other tenses, and the basarse examples and quiz page for more sentences. The Spanish Verb Quiz tests the forms under pressure.

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