Have you returned the book to the library ____?         --- Yes, I have ____ returned it.

—Excuse me, is this your iPad ?          —No, it isn't.             is at home.

---Who’s the most modest boy in your class?---Daniel. He never __________ in public.

 You see, Kevin is writing ______ his left hand.

--- __________ do you chat by QQ with your friend in Shanghai every week?--- Two hours. I have much homework to do every day.