简单英语语法 10 - 时态（现在时，过去时，将来时）

一个动作可能发生在现在，过去，或将来；英语中，动词的时态描述了动作发生的时间。

	现在	过去	将来
一般	finish	finished	will finish
进行中	am/is/are finishing	was/were finishing	will be finishing
已完成	have/has finished	had finished	will have finished
完成进行时(发生在过去,持续了一段时间.可能在过去结束，也可能在现在或将来结束)	have/has been finishing	had been finishing	will have been finishing

有些比较难理解的时态，我们单独解释一下：

现在完成进行时

• It has been raining, and the street is still wet.
• I have been running, and I am still tired.
• She has been practicing the piano, and she is much better now.

现在完成进行时，描述了一个动作，开始发生和结束都在过去，持续了一段时间；但是，这个动作的影响延续到现在。

过去完成进行时

• It had been raining, and the street was still wet.
• I had been running, and I was still tired.
• She had been practicing the piano, and she had gotten much better.

过去完成进行时描述了一个持续的动作，开始发生在过去，在另外一个过去的动作前完成。

未来完成进行时

• By tonight, it will have been raining several hours, and the street will be very wet.
• By next summer, I will have been running for almost a year, and I will be fit and healthy.
• By the time of the concert, she will have been practicing the piano for several months, and she will be much better.

未来完成进行时，描述了一个持续的动作，将要完成在未来。

参考

http://www.talkenglish.com/grammar/simple-tense.aspx
http://www.talkenglish.com/grammar/perfect-progressive-tense.aspx