be +动词不定式主要用法如下:

　　1.表示按计划或安排要做的事。例如:

　　When are you to leave for home?你什么时候回家?

　　She is to get married next month.她下个月结婚。

　　The Queen is to visit Japan in a week's time.女王将于一周后访问日本。

　　这种结构也可用于过去.was / were to do sth. 表示曾经计划要做某事,但不表明计划是否被执行,或表示"命运(即命中注定要发生的事)",而非计划;was / were to have done sth.表示未曾实现的计划。例如:

　　I felt nervous because I was soon to leave home for the first time.我感到紧张,因为我很快就要首次离开家了。

　　We were to have told you, but you were not in.我们本来想告诉你的,但是你不在家。

　　2. 表示"应该",相当于should, ought to。例如:

　　You are to report to the police.你应该报警。

　　What is to be done?应该怎么办呢?

　　3. 表示"必须",相当于must, have to。例如:

　　The letter is to be handed to him in person.这封信必须亲手交给他。

　　You are to do your homework before you watch TV.看电视之前你得先做作业。

　　4. 表示"想,打算",相当于intend, want。例如:

　　If we are to be there before ten, we'll have to go now.如果我们想在十点前到,我们现在就得走.

　　5. 用于第一人称疑问句,表示征求对方意见。例如:

　　Am I to go on with the work?要我继续这项工作吗?

　　What are we to do next?我们下一步该怎么办?

　　6. 用于否定句,表示"禁止",相当于mustn't。例如:

　　The books in this room are not to be taken outside.这个室内的书籍不得带出室外。

　　7.表示"可以,可能",相当于may, can。例如:

　　The news is to be found in the evening paper.这条消息可以在晚报上见到。

　　She is nowhere to be found.在哪里也找不着她。

　　8.were to do sth.用于if或even if / even though从句中,表示对未来的假设。例如:

　　If I were to tell you that I killed him, would you believe me?要是我告诉你我杀了他,你会相信我吗?

　　9. be to blame(该受责备,对某坏事应负责任)这种结构用不定式的主动形式表示被动含义。例如:

　　Which driver is to blame for the accident?这事故是哪个司机的责任?

　　(文/洪德金； 英语辅导报高二版 03~04学年度第40期；版权归英语辅导报社所有，独家网络合作伙伴新浪教育，未经许可，不得以任何形式进行转载。)