新概念英语第三册语法分布|新概念英语第三册语法解析：虚拟语气

虚拟语气用来表达不可能或难以实现的愿望，与事实相反的假设，通常分为基本的三种形式。
　　1. 与现在事实相反的虚拟：
　　If + did / were + ..., ... would/ should/ could/ might + do (动词原形)
　　If I were you, I would go abroad at once. (I am not you.)
　　If he knew it now, he could help me. (He doesn't know it now.)
　　2. 与过去事实相反的虚拟：
　　If + had done + ..., ... would (might) have done ...
　　If I had known your telephone number yesterday, I would have phoned you. (I didn't know your telephone number.)
　　If you had come here a little earlier just now, you might have met her. (You didn't come here earlier.)
　　3. 与将来事实相反的虚拟：
　　(1) If + should + v., ... would + v. (可能性很小)(译作“万一”)
　　If it should rain tomorrow, you could stay at home.
　　If I should fail, what should Ido?
　　(2) If + did / were to + v ..., would + v. (完全不可能)
　　If the sun were to rise in the west, I would lend you the money.
　　If you finished it in 3 minutes, I would give you my car.
　　4. 金牌特殊重点
　　[简单联想记忆]：
　　● 下列动词后的“宾语从句”中需要用虚拟形式，即should + 动词原形，shoud在美国英语中要省略(TOEFL语法考点)。此类常见的动词有：order, ask, decide, demand, require, recommend, suggest(建议), insist(坚决要求), advise, etc.
　　He suggested that we (should) help them with English.
　　The teacher ordered that the homework (should) be finished within half an hour.
　　● 下列名词后的同位语从句中要用“should + 动词原形”(should可省去)的虚拟。此类常见的名词有：suggestion, order, request, demand, importance, proposal.
　　He made a suggestion that we (should) have a fancy dress party.
　　I think it is a thing of importance that it (should) be done soon.
　　● It is / was important / necessary / natural / essential / advisable / strange / surprising, ect. + that +主语+ should + v.
　　It is strange that you should say such a thing.
　　It was important that you should tell me all the information.
　　● wish后的宾语从句中，as if 后的状语从句中，须用下列的虚拟形式：
　　主 + wish+ (that) + 主 + did / were(指现在)
　　had done(指过去)
　　would+ v.(指将来)
　　I wish that I met my uncle now.
　　I wish I had met my uncle yesterday.
　　I wish I could meet my uncle tomorrow.
　　● It is (high) time that ... + did / were ...
　　It is time that you went to bed.
　　● would rather that ... + did / were ...
　　I would rather that you were not here now.
　　● would sooner that ... + did / were ...
　　I would sooner that you got up earlier.
　　I would sooner that you were not my brother.

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