—David，is that man your Chinese teacher?—It___________ be him．He’s having a meeting． 

Now that the sign reads, “No person ______ smoke here”, please choose a seat in the smoking area over there if you _______ smoke.

 My English-Chinese dictionary isn’t in my schoolbag. Where _________ I have put it?

Do some warming up exercise before sports. Or you _______ hurt yourself.

—_____ you please play tennis with me? —Sorry, I _____.