"Maybe he is a policeman."

Translation: Może on jest policjantem.

[AdamMlodoz]

Is there a good time to use 'może' over 'chyba'?

[mihxal]

I would say that "może" expresses wondering about some subject, whereas "chyba" is used when you are not completely sure about validity of information which you give.

[Wlodzimierz96ru]

Czemu nie moźemy powiedzieć: "moze być on jest policjantem?"

[Jellei]

That's a calque from Russian. Polish, if anything, will use "być może".

[IgorZinenko]

On moze jest policjantem. didn't accept this answer

[Jellei]

That doesn't seem correct to me. I think a grammatical way would be "On może być policjantem", but that's "He may be a policeman".

[IgorZinenko]

ok, thanks

[zorrosombra]

Gliny są wszędzie!