------______do you go to the city park?------Usually by bike.
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.
I enjoy playing computer games, but I can't spend too much time ________ that.