There are more than 50 proposals ___at the conference.
4个回答

这里是to引导的介词短语做proposals的后置定语,而这里显然不是主动的动作,所以又用了被动语态.至于D嘛,是现在完成进行时,不适合用在这种语境,意思和时态也不对.

现在完成进行时

其构成形式如下:

I / we / they have

He / she / it has been + 动词的现在分词

1) 表示一个在过去开始而在最近刚刚结束的行动,如:

Ann is very tired.She has been working hard.

Why are you clothes so dirty?What have you been doing?

2) 表示一个从过去开始但仍在进行的行动,如:

It has been raining for two hours.(现在还在下)

Jack hasn’t been feeling very well recently.

3) 表示一个从过去开始延续到现在,可以包括现在在内的一个阶段内,重复发生的行动,如:

She has been playing tennis since she was eight.

4) 现在完成时强调动作行为的结果、影响,而现在完成进行时只强调动作行为本身,如:

Tom’s hands are very dirty.He has been repairing the car.

The car is going again now.Tom has repaired it.