---Do you know where David is? I couldn’t find him anywhere. ---Well. He ______ have gone far----his coat’s still here.

Had Wang Ling received six more votes in the election of out class,she _____our monitor now.       

Doctors say that exercise is important for health, but it _______ be regular exercise. 

I wish you _____ go to the art gallery with us. If there _____ enough tickets, I’d let you know.

—Did you get a ticket then?—Yes,otherwise I _________ the concert last night.