Where’s the zoo?–It’s ________ the post office.[ ]

It was in the hotel _______ I stayed yesterday _______ the accident happened.

Listen! Is that Millie singing?—No. It _____ be Millie. She has gone to Beijing.

_______ homework, we do their homework on Sunday.[ ]

Who’s that man in our classroom? It ________ be Mr. Brown. He is much taller.— You mean the man in white? He is an exchange student from England.