虚拟语气课件if1.ppt

英语动词有三种语气： 陈述语气，祈使语气，虚拟语气。 一、 陈述语气 用来陈述一个事实，或提出一个看法。有肯定，否定，疑问或感叹等形式。 二、 祈使语气 用来表示说话人的请求，命令或劝告等。动词要用原 形，其否定式在动词前加do not. Let me have a try. Don’t be late again. Don’t say it in Chinese. Say it in English. Let’s go and play basketball. 三 虚拟语气 (The Subjunctive Mood)表示说话人所说的 话不是事实,而是一种假设, 愿望, 怀疑或推 测.虚拟语气主要用于if条件状语从句,也可用 于名词性从句等. 虚拟语气If I were you,I would not leave her alone.Our teacher suggested that we go to the library this afternoon. 条件句表示主句的条件,分真实条件句 和虚拟条件句 两种。 真实条件句 表示条件是真的或有可能实现的, 采用陈述语气。 b. 虚拟条件句 表示条件是无法实现或几乎无法实现的, 采用虚拟语气。 四. ‘if ’虚拟条件句的概念 由 ‘if’ 引导的虚拟条件句叫作 ‘if’虚拟条件句 I could easily recognize if I had seen him before. 五. if Sentence Structure  ‘if ’虚拟条件句的结构 a. 表示与现在事实相反 的假设 b. 表示与过去事实相反 的假设 c. 表示与将来事实相反 的假设  1 与现在事实相反 For example: If I had time now, we should read it again. If she knew about it, she would come. If he were here, everything would be all right. a. If they ____ (be) here, they __________ (take) your advice. b. If the world-war _____ (burst) out again, what _____________ (happen) to our people on earth? c. If the policeman ________ (be not) in that room, it ________ (be) very dangerous. d. If I ____ (be) in your position, I _________ (ask) for teacher’s help. 2 与过去事实相反 例如: If he had seen you yesterday, he would have asked you about it. If I had had the money last year, I would have bought a car. If they had known her address, they would have written to her. a. If Tom ________ (be) more careful in the exam, he ________________ (pass) it already. b. If you _______ (get) up earlier, you ________________ (catch) the first train. c. If I _______ (meet) you yesterday, we ______________ (go) to the concert together. 3 与将来事实相反 例如: If it were Sunday tomorrow, I would go to see my friends there. If he got up early, a. If there ________ (be) no natural resource any more, we ___________ (make) use of nuclear power . b. What ____________ (happen) if you __________