—You will never believe that it took us two hours to get to the restaurant.—Really? You ________ in a traffic jam.

---There _____ anybody in the room. --- Why do you say so? --- Because the door is locked.

 —Mr. Smith, why are you always asking me to do the difficult work?—Because you _______ do such a thing and nobody else is fit for it.

Whale beachings（搁浅）_______ be caused by factors such as illness, or disorientation（迷失方向）caused by extra noise in the oceans, ______ shipping or oil and gas drilling.

—Must I return the book tomorrow?—No, you ________.You can keep it for three days.