The theory was attacked when it was first , but gradually it was accepted.

The 29th Olympic Games ____ in Beijing in 2008

Come and join us, Betty!— I’m afraid I can’t. I’m too busy now. If I ______ time, I would certainly go.

David lives on the ________ floor. It is too high, so he has to take a lift every day.

t comes to my hobbies, I like rockclimbing______