The referee must be fair to both teams.
- Sędzia musi być bezstronny.
He must be Tom's brother.
- To musi być brat Toma.
An artist has to have a color-sensitive eye.
- Artysta musi mieć oko do kolorów.
Everyone has to learn the words by heart.
- Każdy musi nauczyć się słów na pamięć.