"The guard wears a hat."

Translation: Ο φύλακας φοράει ένα καπέλο.

[Lng52-._]

Can you also use "φρουρά" for "guard"?

[troll1995]

Yes, in some context. Φρουρά is the total troops at a military post. So η φρουρά της πόλης=the city's guard.

[mizinamo]

So they can't really wear one hat between them :)