It is the first time I ____ to visit the Great Wall.
| A．came | B．come | C．have come | D．had come |
—Hi, Betty．Would you like to go to see a movie with me tonight?
—Sorry, Mary．_________ tomorrow’s lessons, I have no time to go out with you．
| A．Not preparing | B．Not having prepared |
| C．Not to prepare | D．Being not prepared |
He has made a discovery, _________ of great importance to the progress of science and technology．
| A．I think which is | B．which I think is |
| C．which I think it | D．which I think it is |
Rosy came in for _________ coffee and told me _________ firecrackers outside kept her awake last night．
| A．a; the | B．不填; the |
| C．the; a | D．a; the |
—Dad, where on earth did you put my raincoat?
—Oh, Jim．I forgot to tell you．It _________ behind your bedroom door．
| A．would hang | B．has hung |
| C．is hanging | D．hung |
In autumn, _________ the weather is often cool and fine, people living in the city always like climbing hills for outdoor activities to strengthen their health．
| A．which | B．where | C．as | D．when |