四、完成进行时
完成进行时包括现在完成进行时、过去完成进行时、将来完成进行时和过去将来完成进行时。
1.现在完成进行时表示现在以前这一段时间里一直进行的动作,常与all this time， this week， all the morning， recently之类的状语连用。例:
It seems oil from this pipe for some time. We'll have to take the machine apart to put it right.
A)had leaked B)is leaking
C)leaked D)has been leaking
似乎这管子漏油已经好一阵子了,我们得拆开它,再把它装好。（B4，1997.6-45， D对）
In this experiment， they are wakened several times during the night， and asked to report what they .
A)had just been dreaming B)have just been dreaming
C)are just dreaming D)had just dreamt
(B6，1995.6-44， B对)在这个实验中,他们在夜间被叫醒几次,并要他们报告刚才梦见了什么。
2.过去完成进行时主要表示过去某时刻之前一直进行的动作:
It had been raining for a week and the low fields were flooded.一个星期来一直下雨,水位低的田已被洪水淹没。
3.将来完成进行时
表示将来某时前一直进行的动作:
By next summer I shall have been teaching for thirty years. 到明年夏天我就教书满三十年了。
4.过去将来完成进行时
表示从过去某时看来,未来某时以前一直在进行的动作:
He told me that by the end of the year they would have been working together for forty years. 他告诉我说,到年底时他们一起工作就满四十年了。
