IN: Which person is it?
Cheesecake is better than fruitcake because it is gross.
OUT: fruitcake

IN: Which person is it?
The company accepted the resolution because it was well-written.
OUT: the resolution

IN: Which person is they?
The robots tried to negotiate a cease-fire with the squirrel-men, but negotiations broke down when they sabotaged the acorn processing facility.
OUT: The robots

IN: Which person is they?
Chelsea hate Manchester United because they always come in second.
OUT:
Chelsea