9. Mary clapped her hand over her mouth _______ she realized what she had said.
| A．while | B．as soon as | C．suddenly | D．then |
_______ in the computer game, Peter didn’t notice his father approaching.
| A．Being lost | B．Lost |
| C．Losing | D．To lose |
_______ I went to the South Lake in Hanzhong, I was deeply impressed with its beautiful scenery.
| A．For the first time |
| B．The first time |
| C．At first |
| D．It was the first time |
Sheldon could have defeated Howard in the match, but he _______ too careless at the last minute.
| A．is | B．was |
| C．has been | D．had been |
Don’t call me up at this time tomorrow, for I _______ an important test.
| A．will take | B．am taking |
| C．have been taking | D．will be taking |
It’s the third time that Li Ming has been to Xi’an , _______?
| A．isn’t he | B．hasn’t he |
| C．isn’t it | D．hasn’t it |