将来完成时（future perfect tense）是英语十六种时态之一，属于将来时的范畴，顾名思义在未来某个时间点之前已经完成的动作。

一、定义：

表示在将来某一时间以前已经完成或一直持续的动作。

二、结构：

1、肯定句：主语 + will + have + 过去分词...

Linda will have left at eight o’clock.

到八点钟琳达八就走了。

The train will have left by the time you reach the station.

当你到达车站时，火车就已经离开了。

2、否定句：主语 + will not (won't) + have + 过去分词...

Linda will not have left at eight o’clock.

到八点钟琳达还不会走。

The train will not have left by the time you reach the station.

当你到达车站时，火车还不会离开。

3、一般疑问句：Will + 主语 + have + 过去分词...?

Will Linda have left at eight o'clock?

到八点钟琳达就已经走了吗？

Won't the train have left by the time you reach the station?

当你到达车站时，火车不会已经开了吗？

4、特殊疑问句：特殊疑问词 + will + 主语 + have + 过去分词...?

When will Linda have left?

到什么时候琳达已经离开了？

Why will it have got colder by May?

为什么到五月份天气会变冷？

三、基本用法

1、在未来某个时间或事件之前结束的动作或事件。

You will have arrived by then.

到那时你已经到了。

They will have dressed up by the time you reach home.

你到家时，他们会打扮好的。

He will have learned all the songs by heart before anyone else does.

他会比其他人先把所有的歌都背熟。

2、表示推测

I don’t think Leo will have cleaned the house completely by the time we reach.

我认为我们到达的时候利奥不会把房子打扫干净。

Considering how things are going on now, they will not have finished their homework by tomorrow.

考虑到现在的情况，他们明天不会完成作业。

四、时间关键词

将来完成时常见的时间关键词有：before，by the time，by + 特定的时间，when，after，by + 日期或年份，by then，until，by the end of，till，by the year 2022，……。

五、时态区分

将来进行时和将来完成时是属于未来时期的两种时态。必须准确理解它们，以便在书面和口语中正确使用和使用它们