1、be +动词不定式用法以及几种表示将来时态的辨析be +动词不定式（即 be + to do sth.）有以下几种含义： 1.表示 “将”、 “计划”、 “安排”。(意思接近于 be going to) Their daughter is to get married soon. It was the last film at the cinema，which was to close next day. 注：was/ were to have done, 表示 “本打算”、 “本计划”或“本应当” 做的事而没有做成或没有发生。如: I was to have seen him last We
2、dnesday, but he didnt come. We were to have been married last year.2.表示义务,应该,接近于should,must,ought,have to No one is to leave the building. 谁也不得离开这楼房。 You are not to smoke in this room.=You are not supposed to smoke in this room. You are to be back by 10 oclock. 你必须十点以前回来。 3. 表示 “命运”, 将来必然要发生的事, 译作 “
3、注定”。如： They said goodbye, little knowing they were never to meet again. 4.用于否定句，表示“禁止”，相当于 mustnt。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。 You are not to smoke in the reading-room.你不可以在阅览室里吸烟。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?要我继续完成这项工作吗？ What are we
4、to do next?我们下一步该怎么办6.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。 Such people are to be found everywhere.这种人到处都有。 She is nowhere to be found.在哪里也找不着她。 特殊结构：be to blame(该受责备，对某坏事应负责任)be to let(待出租)两种结构中，用不定式的主动形式表示被动含义。例如： Which driver is to blame for the acc
5、ident?这事故是哪个司机的责任？This house is to let.这房子要出租。辨析：1.Will表示未经事先考虑而只是说话时临时作出的决定，表示说话人认为，相信，希望或假定要发生的事，也可表示倾向性或规律性，事物的固有属性或必然趋势。注：在含有条件状语从句的主从复合句中，主句一般不用be going to，而常用 will（第一人称用 shall） 。如：The football match will be put off if it rains tomorrow. 如果明天下雨，足球赛将被推迟举行。2.Be going to 表示事先经过考虑，或有迹象表明某事即将发生或肯定发生
6、，一般带有时间状语，常用于口语。3.一般现在时 表按时刻表或按规定发生的事4.现在进行时 表按计划、安排近期发生的动作(只限于 come, go, leave, arrive, start, move, sail, fly, travel, stay 等）5.be about to do 即将 常和 when 引导的时间状语连用(此形式不能与具体时间状语连用）小试牛刀：1.The students were told that they _ at the school gate at 2:00 the following afternoon. A. met B. would meet C. w
7、ere to meet D. were met 2. The house _ ready today but as there has been a builders strike it is still only half finished. A. is B. was to be C. was D. was to have been 3.In such dry weather, the flowers will have to be watered if they _. A. have survived B. are to survive C. would survive D. will s
8、urvive 4.How _ I _ what has become of him? A. am; to know B. am; knowing C. was; to know D. will; know 5. _ he _ tomorrow, I would go to meet him at the station. A. Were; to come B. Was; coming C. Did; come D. Would; come答案解析：1. be to do 表将来, 时态需一致, 用 were to meet; 2. 用 was 表明已经过去, to have been., 虚拟语气 , 与事实相反, 表 明本该.却没.; 3. if 条件句, 用不定式现在时态 be to do 表将来; 4. be to do, 表示可能会., =我怎么知道他的遭遇如何? 5. 虚拟语气, 用 were 不用 was, 即=If he were to come. 助动词 were提前，省略 if
