It was very late, but the teachers were ________ working hard in the office.

—We are free this afternoon. Let’s go to play computer games.—Well. I think I’d better watch an English program _________.

--Would you like _______ tea?        --Yes, _______.

Please don’t drop litter _______, you should throw it into the dustbin _______.

--_____is the post office ?--- Go straight and turn right.