Learn Dutch: De jongen wast zich. - The boy washes himself.

zich means himself (or herself, itself, themselves). If we used hem (De jongen wast hem), it would mean the boy is washing another male person. Because he is doing the action to his own body, we must use the reflexive pronoun zich.

Is zich only used for himself?

No! zich is the standard reflexive pronoun for all third-person subjects. Depending on who is doing the action, it can translate to himself, herself, itself, or themselves. It is also used with the formal you (u).

In English we can often just say The boy washes. Can we drop zich in Dutch?

Not if he is washing himself! If you just say De jongen wast, a Dutch speaker will expect you to say what object he is washing (like the dog or the dishes). You need zich to show the action reflects back onto the boy himself.

Why does the verb wast end in a -t?

The subject is De jongen (The boy), which acts as a he (hij). For he, she, or it, we take the stem of the verb (was) and add a -t to the end, giving us wast.