1、 1 选修二选修二 U1 单元语法单元语法表语从句表语从句 一、一、概念：概念： 表语从句是在复合句中作表语的名词性从句。放在系动词之后,一般结构是“主语+系动词+表语从句”。可以接表语从句的连系动词有 be, look, feel, keep, become, get, prove, remain, seem 等。 二、二、可以接表语从句的系动词：可以接表语从句的系动词： be 动词 am，is，are 感官动词 look，sound，taste，smell，feel 持续性动词 keep，stay，remain 变化系动词 get，become，grow，turn，go 表象系动词 see
2、m，appear 终止系动词 prove，turn out 三、表语从句的引导词三、表语从句的引导词 1. 由连词 that，whether 引导的表语从句 that 无实际意义，只起连接作用，而 whether 有实义，意为“是否” 。此时主句的主语通常是抽象名词，如 problem，result，chance，suggestion，question，reason等。表从对主句主语进行解释、说明等。 例：事实是他不想加入我们。 The fact is that he doesnt want to join us. 我的建议是我们应该告诉他。 My suggestion is that we
3、should tell him. 问题是这部电影是否值得看。 The question is whether the film is worth seeing. 问题还是他们能否帮我们。 The problem remains whether they will be able to help us. 【注意】whether 可引导表语从句，但 if 不行。 2 2. 由连接代词引导的表语从句 由连接代词 who， what， which， whose， whom， whatever， whichever， whoever，whomever 等引导的表语从句，在表语从句中有词义，句子中担任成分
4、，不能省略(有 ever 的为泛指， “无论.” 。)。 例：问题是谁能做这项工作。 The problem is who can do the work. 这是我想强调的。 Thats what I want to stress. 3. 由连接副词引导的主语从句。 连接副词 when，where， how， why，whenever，wherever 等引导的表语从句，连接副词有具体含义，且在从句中作状语。 例：这就是他没有来的缘故。 Thats why he didnt come. 问题是我们如何找到他。 The problem is how we can find him. 4. 由连接
5、词 because，as if / as though 等引导的表语从句 例：这是因为我们从未想过此事。 Thats because we never thought of it. 好像他不知道答案。 It seems as if he didnt know the answer. 四、四、注意注意事项：事项： 1. 判断正误：The question is when can we get a pay rise. （ ） The question is when we can get a pay rise. （ ） 结论：_表语从句一定要用陈述语序. 2. 判断正误：The question
6、is if the enemy is marching towards us. （ ） The question is whether the enemy is marching towards us. （） It looked as if he had understood this question. （） 3 结论：if 不能引导表从，要用 whether 。(as if 例外） 3. as if/ as though 引导表从的时态问题 填空： （1）Dark clouds are gathering. It seems as if it _is going to rain_( rai
7、n ) （2）You will feel as if you _were_(be) at home here. （3）Local people said after the storm it was as if there _had been_(be) a nuclear explosion. 结论：as if 引导的表从的内容有明显的依据，很有可能发生，就用陈述语气。反之，则用虚拟语气。虚拟语气的构成：比较主从句的两个动作，同时发生，就用一般过去时表示虚拟 （be 动词只能用 were） ； 从句动作明显发生在主句动作之前，就用过去完成时表虚拟。 4. 判断正误：We received th
8、e order that we left at once. （） We received the order that we should leave at once. （） 结论： 主句的主语是要求、 建议、 命令等词， 表语从句的谓语动词要用 “should + 动词原形”；其中，should 可以省略。这类词有：request /requirement（要求） 、proposal/ advice/ suggestion/ recommendation（建议） 、order/ instruction（命令） 5. 表从的常见句型： （1）The reason is that. （原因是.）
9、 （2）This/ That is why. （这是.的原因， 指由于各种原因所造成的结果。 ） （3）It/ This/ That is because. （这是因为.，指原因或理由。 ） （4）That is the reason why. = Thats why. 课后练习课后练习 一、填入恰当的连接词 1. _ I want to know is _ road we should take. 2. The result of the invention of steam engine was _ human power was 4 replaced by mechanical powe
10、r. 3.What a mess! You are always so lazy! Im not to blame, mum. I am _ you have made me. 4. The main question is _ you want your arms inside or outside the sleeping bag. 5. As John Lennon once said, life is _ happens to you while you are busy making other plans. 6. Please put the medicine on the top
11、 of the shelf. Its _our children cant reach it. 7. The last time we had great fun together was _ we were visiting the Water Park. 8. The little girl _ got lost decided to remain _ she was and wait for her mother. 9. A ship in harbour is safe, but thats not _ ships are built for. 10. Actually, girls
12、can be _ they want to be just like boys, _ it is a pilot, an astronaut, or a manager . 11. From space, the earth looks blue. Thats _about 71% of its surface _(cover) by water. 12. He was born here. Thats _ he likes the place so much. 13. It seems _ the brain is preserving its most important memories
13、. 14. The teachers requirement is _ we _(recite) the passage in twenty minutes. 15. All she is worried about is _ he is all right. 16. Do you think it is wise for Chinese mothers to try to do everything for their children? No, thats _ they are mistaken. 17. Sorry, he cant go with you. The reason is
14、_ he has something to do tomorrow. 18. The reason _ he is absent from the meeting is _ he is ill. 19. He is ill. Thats _ he is absent from the meeting. 20. He is absent from the meeting. Thats _ he is ill. 21. You are saying _ we born equal and thats_ I agree. 22. The question is _ we will have our
15、sports meeting next week. 5 23. He was ill. Thats _ he was sent to the hospital. 24. Thats _ the direct current always flows in a wire in one direction. 25. This is _ heat can melt ice, vaporize water and cause bodies to expand. 二、翻译句子。 1. 他已经不是以前的他了。 _ 2. 麻烦的是我把他的地址丢了。 _ 3. 问题是我们应当相信谁。 _ 4. 问题是什么时候
16、他才能到达酒店。 _ 5. 我们似乎应该对此事负责。 _ 6. 看起来好像要下雪了。 _ 7. 你爸爸想知道的是你跟同学们相处得怎么样。 _ 8. 我的建议是我们应该帮他想个办法。 _ 9. 原因是你不信任她。 _ 10. 你说我们生而平等，那是我同意你的地方。 _ 答案： 一、填入连接词： 1. What，which 2. that 3. what 4. whether 5. what 6. where 7. when 8. who, where 9. what 10. whatever, whether 11. because, is 6 covered 12. why 13. that/
17、as if 14. that, (should) recite 15. whether 16. where 17. that 18. why, that 19. why 20. because 21. that, where 22. whether 23. why 24. because（那是由于直流电在导线中总沿着一个方向流动。 ） 25. why（那就是热能使冰融化，使水蒸发，使物体膨胀的原因。 ） 二、翻译句子： 1. He is no longer what he was. 2. The trouble is that I have lost his address. 3. The q
18、uestion is who (m) we should trust. 4. The problem is when he can arrive at the hotel. 5. It seems that we should answer for this. 6. It looked as if it was going to snow. 7. What your father wants to know is how you are getting on with your classmates. 8. My suggestion is that we should come up with an idea for him. 9. The reason is that you dont trust her. 10. You are saying that we born equal and thats where I agree.