1. Formal and Plural Commands
Form affirmative formal commands by substituting the -o of the present-tense yo form of a verb with an -e for -ar verbs, or with an -a for -er and -ir verbs.

2. Infinitive Yo Form Stem Sing. Formal Command Plural Commands Hablar
Hablo
Habl-
Hable Ud.
Hablen Uds.
Comer
Como
Com-
Coma Ud.
Coman Uds.
Escribir
Escribo
Escrib-
Escriba Ud.
Escriban Uds.
Cerrar
Cierro
Cierr-
Cierre Ud.
Cierren Uds.
Volver
Vuelvo
Vuelv-
Vuelva Ud.
Vuelvan Uds.
Seguir
Sigo
Sig-
Siga Ud.
Sigan Uds.

3. Irregular Formal and Plural Commands
Attach object and reflexive pronouns to the end of affirmative formal commands. A written accent mark may be required in order to maintain the original stress of the verb.

4. Infinitive
Ud. Command
Uds. Command
Dar
Dé ud.
Den uds.
Estar
Esté Ud.
Estén Uds. Ir
Vaya Ud.
Vayan Uds.
Saber
Sepa Ud.
Sepan Uds.
Ser
Sea Ud.
Sean Uds.

5. Suggesting what to do: nosotros commands
Using a nosotros command allows you to suggest that others do some activity with you and is equivalent to saying “lets (do something)” in English. Form the nosotros command by substituting the -o of the present tense yo form of a verb with emos for most -ar verbs, or -amos for most -er and -ir verbs.

6. Infinitive
Yo Form
Nosotros Command
Hablar
Hablo
Hablemos
Comer
Como
Comamos
Escribir
Escribo
Escribamos
Cerrar (ie)
Cierro
Cerremos
Volver (ie)
Vuelvo
Volvamos
Divertir (ie,i)
Divierto
divirtamos

7. Talking about whom and what you know: conocer and saber
Both verbs are irregular in the present tense.
Use saber to talk about facts that someone may or may not know.
Use conocer to discuss whether someone is familiar with (or acquainted with) people places or things.

8. Saber Conocer Sé Sabes Sabe Sabemos Sabéis Saben Conozco Conoces
Conocemos
Conocéis
Conocen

9. Telling someone what not to do: negative commands
The formation of a negative Ud. Or Uds. Command or a negative nosotros/ as command is the same as for an affirmative command, but with no before the verb. The negative nosotros/ as command for ir is one exception.