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Ser Commands Practice

Ser (to be (essence)) in the commands: 14 free exercises with an explanation after every answer, plus the full conjugation table.

14 exercisesIrregularB1 – B2 level
IWhat to watch for

The affirmative tú command of ser is sé — one of the eight short irregular commands, and the only one that is spelled exactly like a form of another verb: sé also means I know, from saber. Context decides: sé paciente is an order, no sé nada is a statement.

Everything else comes from the subjunctive stem se-: no seas for negative tú, sea for usted, seamos for nosotros, sean for ustedes. Because those are subjunctive forms already, usted and ustedes keep the same shape when the command turns negative — no sea tan severa — while tú swaps sé for seas.

IIConjugation
serCommands
tú (affirmative)
tú (negative)
no seas
usted
sea
nosotros
seamos
ustedes
sean
Fully irregular in the present, preterite, and imperfect — the forms have to be memorized.
IIIPractice exercises

Practice.

Answer first, then read the explanation. Don't skip it — that's the whole point.

Exercise 01 of 14Tag: Irregular tú command
Fill in the blank

_____ paciente con ella, acaba de empezar en el puesto. (ser)

Be patient with her, she has just started in the job.

Exercise 02 of 14Tag: Negative tú command
Fill in the blank

_____ tan duro contigo mismo, has hecho lo que podías. (ser)

Don't be so hard on yourself, you did what you could.

Exercise 03 of 14Tag: Usted command
Fill in the blank

_____ tan amable de esperar aquí un momento, por favor. (ser)

Would you be so kind as to wait here for a moment, please.

Exercise 04 of 14Tag: Nosotros command
Fill in the blank

_____ realistas: no vamos a terminar esto hoy. (ser)

Let's be realistic: we are not going to finish this today.

Exercise 05 of 14Tag: Ustedes command
Fill in the blank

_____ puntuales, la ceremonia empieza a las siete en punto. (ser)

Be on time, the ceremony starts at seven sharp.

Exercise 06 of 14Tag: Irregular tú command
Fill in the blank

_____ sincero conmigo aunque la verdad duela. (ser)

Be honest with me even if the truth hurts.

Exercise 07 of 14Tag: Negative tú command
Fill in the blank

_____ el último en enterarte de lo que pasa en tu propia casa. (ser)

Don't be the last to find out what is going on in your own house.

Exercise 08 of 14Tag: Usted command
Fill in the blank

_____ breve en la presentación, tenemos poco tiempo. (ser)

Please be brief in the presentation, we are short on time.

Exercise 09 of 14Tag: Irregular tú command
Fill in the blank

_____ tú mismo en la entrevista, es lo que buscan. (ser)

Be yourself in the interview, that is what they are looking for.

Exercise 10 of 14Tag: Negative ustedes command
Fill in the blank

No _____ tímidos: pregunten todo lo que quieran. (ser)

Don't be shy: ask anything you like.

Exercise 11 of 14Tag: Negative tú command
Fill in the blank

_____ injusto con el árbitro, la jugada era muy difícil. (ser)

Don't be unfair to the referee, the play was very difficult.

Exercise 12 of 14Tag: Nosotros command
Fill in the blank

_____ prudentes con el gasto hasta que cobremos. (ser)

Let's be careful with spending until we get paid.

Exercise 13 of 14Tag: Irregular tú command
Fill in the blank

_____ generoso con las propinas, aquí cuentan mucho. (ser)

Be generous with tips, they matter a lot here.

Exercise 14 of 14Tag: Negative usted command
Fill in the blank

No _____ demasiado severa con los alumnos nuevos, profesora. (ser)

Don't be too strict with the new students, professor.

Every answer is explained

Not just a green check. A short paragraph telling you why.

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