—What a beautiful dress you are wearing today!—_________. It’s nice of you to say so.
—________ English book is this? —Maybe it is Lucy's.
Yesterday something ________ happened. We didn't know what it was.
This coat ________ be Tom's. He doesn't like the color at all.
—Is Mr. Smith over there? —It ________ be him. He has gone to Beijing on business.
-was the car invented? --It was invented in 1983.