She hurried to her office by taxi, only _____ that the key had been left at home.
| A．finding | B．found | C．to find | D．find |
People are living in world where mouse clicks rule our life, so online searches have become _______must.
| A．the; / | B．/;a | C．a; a | D．a; the |
My friend has returned from the UK. Sheat Oxford for four years, during which we communicated with each other on the Internet.
| A．studied | B．has studied |
| C．had studied | D．has been |
Mr. and Mrs. James feel more comfortable on a ship than they would do if they _________ any other way．
| A．travel | B．are travelling |
| C．have travelled | D．travelled |
—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 |