题目内容
For some time the expert __________ people of the health risks caused by passive smoking. He says he won't stop until all the smokers around him decide to quit smoking.
| A．is warned | B．is warning | C．has been warning | D．has been warned |
C
解析考查时态：句意是：有一段时间这个专家一直在警告被动吸烟引起的健康危害，他说知道身边所有的抽烟者都戒烟了他才停止。由此可知警告这个动作是从过去到现在一直在做，而且还要继续，符合现在完成进行时的用法。选C。
--- Oh! You bumped me!
--- I am sorry. But I to catch the coming bus.
| A．try | B．tried | C．am trying | D．was trying |
The train_____at the present speed until it reaches Chicago at eleven o’clock tonight.
| A．has gone | B．will be going | C．went | D．goes |
He to keep this book for a month.
| A．will allow | B．will be allowed | C．allows | D．allowed |
Henry goes to a free class every Sunday afternoon which______at 4 pm.
| A．starts | B．will start | C．is to start | D．started |
--- Hello, I to ask if I can book two tickets for tonight’s film.
--- Sorry, we’ve already sold out.
| A．phone | B．will phone | C．am phoning | D．have phoned |
I know a little bit about the city as I __________ there for one year in my youth.
| A．am studying | B．had studied | C．studied | D．have studied |
When I ________ home, I caught a thief stealing from a passerby.
| A．headed | B．was heading |
| C．has headed | D．had headed |
His sister left home in 1998，and ________ since.
| A．had not been heard of | B．has not been heard of |
| C．had not heard of | D．has not heard of |