一、過去將來完成時和將來完成時從字面的意思上看，它們的區(qū)別就在于時間，過去將來完成時，強調的是過去的時間，而將來完成時強調的是將來的時間，兩者都是在將來的時間事情已經完成，例如：
1. The day was not so far when we would have finished this project.
我們完成這個項目的日子不遠了。
2. He said he would have done with my camera by the end of next month.
他說到下月底就不用我的照相機了。

二、將來完成時是用在表示在將來某一時間以前已經完成或一直持續(xù)的動作。經常與before+將來時間或by+將來時間連用，也可與before或by the time短語引導的現在時的從句連用。例如：
1.Before long he will have forgotten all about the matter.
不久他就會全然忘記這件事的。
2.He is somebody now. He will not have remembered his old classmates.
他現在是一個有身份的人了，他可能不會記得老同學了。
3.Will you have known Kevin for 10 years next month?
到下個月你認識凱文該有10年了吧？
4.Pick me up at 8 o'clock,I will have had breakfast by then.
早上8點鐘你來接我，到時我已經吃完早飯了。
5.We will have learned 12 units by the end of this term.
到這個學期末，我們將學完12個單元。
6.By the time you get home I will have cleaned the house from top to bottom.
你到家之前我將把房子徹底打掃一遍。
7.You will have heard of this, I guess.
屆時我想你已經聽說過這件事了。
8.I am sure he will have got the information.
我相信他一定會得到這個信息。
9.We will have been married a year on June 25th.
到6月25日我們倆結婚就滿1年了。
10.They will have been married for 20 years by then.
到那時他們倆結婚就滿20年了。