—Can your friend sing?--______.

---Can you play the guitar?
---________.

--- Whose backpack is this?
--- It       be Mary’s. She is looking for hers.

—Sandy, we need an actor for the action movie. __________ you play kungfu?
—Sorry, I can’t.

—How wonderfully Jim is swimming in the pool！
—It ______ be Jim. I am not sure.

 The book        Jenny’s. There is her name on it.

—Dad,mustIpractice thepianotoday?
—No,you  _.You may doit tomorrow.

— Could I use your mobile phone, Tim?
— Of course you can, but you ________ use it in the reading room.

— Listen! Is that Millie playing the piano in the room?
— No, It_____ be Millie, she has gone to London.

--- Can I walk across the road now, Mrs. Chen?
---No, you ______. You have to wait until the light turns green.