同位语从句与定语从句异同一. 同位语从句与定语从句的相似点1．同位语从句与定语从句都可以译成定语同位语从句：The news that our team has won the final match is encouraging.我们队取得决赛胜利的消息令人鼓舞。
定语从句：The news that you told us is really encouraging.你告诉我们的消息真的令人鼓舞。
2．同位语从句与定语从句都可以用that引导同位语从句：The suggestion that students should learn something practical is worth considering.学生应该学些实用的东西的建议值得考虑。
定语从句：The suggestion that is worth considering is that the students should learn something practical.值得考虑的建议是学生应该学些实用的东西。
3.同位语从句与定语从句和其它名词性从句一样也要用陈述语序同位语从句：Have you any idea where have they gone？(语序错误)Have you any idea where they have gone？你知道他们去哪里了吗？定语从句：Do you remember the day when did you join our club?（语序错误）Do you remember the day when you joined our club?你记得自己什么时候参加我们俱乐部的吗二.同位语从句的独特用法1.同位语从句有时也可以用whether来引导,但是定语从句则一般不用whether来引导。
例如: The problem (of) whether they could finish the project is very important.他们是否能够按期完成那个项目,这个问题非常重要。
2.某些名词后的同位语从句，其谓语动词应用虚拟语气形式：（should）+ 动词原形。
常见的名词有advice, suggestion, order, demand, proposal, request等。
例如：The advice that he (should) be invited to the party was taken.应该邀请他到晚会的建议被采纳了。
三.同位语从句与定语从句的区分方法1.从从句与先行词的关系区分同位语从句与定语从句从语义角度看，同位语从句与先行词之间存在的是同位或等同的关系，而定语从句与先行词之间存在的是所属关系，表示“……的”，起修饰限定作用。
例如：同位语从句：The news that she had passed the exam made her parents very happy.她考试及格的消息使她父母很高兴。
（that之后是news的具体内容）定语从句：The news that he told us interested all of us.他告诉我们的消息使大家都感兴趣。
（that之后是对news的解释）2.从引导词的作用区分同位语从句与定语从句从语法角度来看，引导同位语从句的that是连词，只起语法作用，用来连接同位语从句，在从句中不充当任何成分；而引导定语从句的that是关系代词，它除了起引导从句的语法作用之外，还要在从句中充当句子成分主要是作主语或宾语。
例如：同位语从句：The fact that he succeeded in the experiment pleased everybody．他实验成功这个事实使我们大家很高兴。
（that只起连接作用）定语从句：The fact that (which) we talked about is very important．我们所谈论的那个事实很重要。
（that在从句中作about的宾语）3.从先行词的词性区分同位语从句与定语从句从先行词的词性来看，同位语从句的先行词大都为抽象名词，而定语从句的先行词可以是名词，也可以是代词。
例如：同位语从句：There is no doubt that the price of wheat will go up.毫无疑问，小麦的价格将会上涨。
(doubt为抽象名词)定语从句：Those who were against the plan raised their hands.那些反对这个计划的人举起了手。
(Those为代词)4.从that可否省略区分同位语从句与定语从句从that可否省略来看，同位语从句的that一般不可以省略，但是定语从句中的关系代词如果在从句中充当宾语，在非正式用语中常常可以将关系代词that省略。
例如：同位语从句：We heard the news that our volleyball team had won the match.我们听说了我们排球队获胜的消息。
（that不可省略）定语从句：This is the very book (that) I’m looking for.这正是我要找的那本书。
（that作for的宾语，可以省略）5.从引导词与先行词的关系区分同位语从句与定语从句who, which, what, when, why, how, where等词都可以用来引导同位语从句，但它们的用法和用作关系代词或关系副词时引导定语从句的用法不同：引导同位语从句的关联词是对先行词的具体内容进行进一步的解释说明，与先行词不存在指代关系；而引导定语从句的关系代词或关系副词不但在从句中充当成分，而且与其修饰的先行词指代的是同一个人或者事物。
例如：同位语从句：He has solved the problem why the radio was out of order.他解决了收音机为何出故障的问题。
(why引导的是同位语从句)定语从句：The reason why he was late for class is quite clear.他上课迟到的原因显而易见。
(why引导的是定语从句)同位语从句/定语从句辨析小练一、指出同位语从句和定语从句，并翻译。
1. We are not looking into the question whether he is worth trusting.2. Word came that he had been abroad.3. The order that we received yesterday was that we should send a few people to help the other groups.4. I made a promise that if anyone set me free I would make him very rich.5. The mother made a promise that pleased all her children.二、单项选择1. It was true _____ Alice did surprised her mother.A. thatB. whatC. that, whatD. what, that2. Does ____matter much ____he can’t come to the meeting.A. it, ifB. that, ifC. it, whetherD. this, whether3.--What are you anxious about? -- ____A. How can we succeedB. Whether we can succeedC. When can we succeedD. That we can succeed4. The reason ____the little actress has been such a success is ____she is both clever and hard-working.A. why, whyB. why, thatC. that, becauseD. for, because5. ____leaves the room last ought to turn off the lights.A. WhoB. WhoeverC. AnyoneD. The person6. I really don’t know _____I had this photo taken.A. where it was thatB. it was thatC. where it wasD. it was why7. Dr. Black comes from either Oxford or Cambridge. I can’t remember ____.A. whereB. thereC. whichD. that8.--What do you think of China? --____different life is today from ____it used to be.A. How, whatB. What, whatC. How, thatD. What, that9. Give this to ____you think can do the work well.A. whoB. whomC. whoeverD. whomever10.____troubles me is ____I can’t learn all these En glish idioms by heart.A. That, thatB. What, whatC. That, whatD. What, that11. The fact ____ she works hard is well known to us all.A. thatB. whatC. whyD. which12. The news ____ he was kidnapped surprised us greatly.A. whatB. thatC. whyD. when13. His suggestion ____ the meeting be delayed was turned down.A. whichB. thatC./D. it14. I have no idea ____ he will start.A. whenB. thatC. what D ./15. He often asked me the question ____ the work was worth doing.A. whetherB. whereC. thatD. when1—5 CABBB 6—10 ACACD 1-15 ABBAA三、用适当的连接词填空：1. It worried her a bit _____ her hair was turning gray.2. I have no idea _____ we can do with these waste materials.3.____the doctor really doubts is____my mother will recover from the serious disease soon.4. It is hoped____nature will never be destroyed.5. ____do you guess will give a talk on English tomorrow?6.-- I drove to Zhuhai for the air show last week. -- Is that ____ you had a few days off?7. Word came____I was wanted at the office.8. Do you know ____of them will be our new headmaster?9. The teacher didn’t tell me ____we were wrong.10. It’s generally considered unwise to give a child ____he or she wants. ?1. that2. what3. what, whether4. that5. who6. why7. that8. which9. where 10. Whatever。