—What do you think people can do for their aged parents?—They_________ do anything except to be with them and be themselves. 

You look quite tired. You’d better _____a good rest.

—Listen！Helen is singing in the next room.—It _____be Helen .She has gone to Beijing.

— Mum, my friends are waiting for me outside. May I go out to play with them?— Yes, you        , but be careful, please.

----Must I hand in our homework today?--- No, you ______.

The students        be in the classroom because there are lights in it.

—Must I take out the trash?—No,  you ________.

It’s already half past seven. You ________ get up quickly.

——Dad, must I finish my homework today?——No, you         . You may do it tomorrow.

It’s time _____ class. You must _____ the classroom.

—Look! A book is on the floor. Whose is it?—It ______ be Rick’s. It has his name on it.

—Must I buy lunch at school?—No, you needn’t. You __________ bring your own lunch if you want to.

There's enough time for you to go to the airport.You        hurry now.

—Must I return the book this week?— No, you ____. You can ____ it for 20 days.

 ---There is somebody knocking at the door. Who________ it be?---I’m not sure. It ________ be a postman.

The book ________ be Tom’s. Look! His name is on it.

— Mum, will you buy me the new iPad after the Entrance Examination?— I’m afraid I ________, dear. We are short of money now.

---Is that Lucy’s sister, Lily?---No, it _______ be her. She has gone to English.

）The red bike _______be Hu’s.  She has a blue bike.

--- Do you have any plans for this weekend?--- I’m not sure. I _____ go climbing Mount Baoshi.