There is a verbal structure in Spanish that is used to express a command:
With this structure we don't need to specify who the command is directed to, so it is used to ask whoever is in front of you to do something, it can be one or more people.
Have a look and listen to these examples:
When the verb is a pronominal verb, remember to keep the reflexive pronoun "se".
It is also acceptable to use the specific reflexive pronoun
- te (i.e when the command is directed to one person)
- os (i.e when the command is directed to more than one person)
We don't use this type of command to ask someone to "not" do something, for example:
In these cases, we would use the more usual form for negative commands. See also Forming simple negative commands : No + El Presente de Subjuntivo (present subjunctive)
As a general rule, remember that the verbal form after a preposition (a, de, por, para, en...) is an infinitive. Have a look at this example:
¡Todos a bailar! (Let's all dance!)
¡Todos a bailando!
¡Todos a bailamos!