es (agent inespecífic)

Use impersonal es to speak about what people do without naming an actor: aquí es treballa molt. With an intransitive verb there is no direct object that could become a grammatical subject. The form is not an instruction that literally names a person called es.

A general description such as en aquesta feina es viatja molt applies to an unspecified class of workers. It does not identify a hidden plural subject with which the verb must agree. By contrast, es revisen expedients is passive and has a plural patient subject. In instructions, an active personal form can make responsibility clearer when a specific reader must perform the action; choose impersonality only when that generality is intended.