将来完成时(1) 表示在将来某一时间之前完成的动作，往往对将来某一时间产生影响。I shall have finished reading the book by the end of this week. 我将在本周末前读完这本书。Before long, he will have forgotten all about the matter. 过不久，他很快就会把这件事全然忘记。(2) 表示持续到将来某时的动作或状态。如：By the time he graduates, he will have studied French for four years. 到他毕业的时候，他学法语就满四年了。By the time Pierce comes back from the meeting, we will have waited here for three hours. 到皮尔斯开会回来的时候，我们已经在这儿等了三个钟头了。
