虚拟语气的用法.doc

虚拟语气的用法 一、 在条件句中的应用 从句 (if) 主句现在 过去式 (be were) would/ could/might do 将来 过去式/were to do/ should do would /could/might do过去 had done would have doneNote: 1. 如果从句和主句的动作发生时间不一致，动词的形式要根据表示的时间来调整，可用错综时间条件句。- Amy would be alive today if the doctor had come sooner last night.2. 假设的情况不以条件从句表示出来，而是通过介词短语或上下文表现出来，可用含蓄条件句。- Without music, the world would be a dull place. - Such mistakes could have been avoided (if we had been more careful). 3. 如果从句中含有were, had,或should，有时可把if省略，但要把were, had, should放在主语前，引起倒装。- Should there be a flood, what would we do?4. but for/ without= if it had not been for要不是 but that = if .had not二、 在某些从句中的应用1. wish，if only 后的宾语从句 现在 过去时 过去过去完成时 将来 would/ could/should do 2. would rather, would sooner, would just as soon (宁愿.)后的宾语从句对现在或将来的希望，用过去时，对过去的希望，用过去完成时。- I can go myself but I would sooner you went.3. 用于表示命令，决定，建议等词后的that-分句中1) suggest, propose, recommend, advise, order, insist, require, request, demand, ask, decide, prefer, urge (敦促) + that(should) do这些词用于被动或名词形式也用虚拟。2) It is + advisable, desirable, important, vital, necessary, essential, strange, urgent, obligatory, proper, appropriate +that (should) do4. as if/ as though1)从句的动作与主句的动作同时发生，用过去时。（如表示思想、内心活动） - He talked as if he knew where they were.2)从句的动作发生在主句之前，用过去完成时。 - They talked / are talking as if they had been friends for years.5. It is time / high time (that)+ 过去时6. whether在选择条件让步分句中，如果有be，可用动词原形(正式语体中)。 - Whether he be friend or enemy, the law regards him as a criminal. = Be he friend or enemy, the law regards him as a criminal.Exercise1) If the sun _ tomorrow, what would we do?A. would not rise B. should not rise C. had not risen D. does not rise2) _ electronic computers not been used, it would have taken them a long time to solve the complicated problem.A. If have B. Have C. If had D. Had3)_ for your laziness, you could have passed the exam.A. It were not B. Werent it C. Had it not been D. Had not it been4) But that he had been prevented, he _ his design.A. would accomplish B. had accomplished C. accomplished D. would have accomplished5) If he had received six more votes, he _ our chairman now.A. would be B. would have been C. must have been D. were6) I would rather they_ tomorrow.A. will come B. come C. came D. would come7) I wish I _ with them at that time.A. were B. had been C. would be D. were to be8) Without their help, we _ the work.A.