The present

The verb forms are the present, the past and the past participle.

become, became, become - stawać się

The present

I want to become a policeman.
Chcę zostać policjantem.

The past

When I was a teeneger I became rich.
Kiedy byłem nastolatkiem zostałem bogaty.

The past participle

I become rich.
Bogacę się.