Unit 4 Natural DisastersPeriod 3 Discovering Useful Structures【教材分析】This teaching period mainly deals with the grammar: the restrictive relative clauses.This period carries considerable significance to the cultivation of students writing competence and lays a solid foundation for the basic appreciation of language beauty. The teacher is expected to enable students to master this period thoroughly and consolidate the knowledge by doing some exercise of good quality.【教学目标与核心素养】1. Get students to have a good understanding of the basic usages of the restrictive relative clauses.2. Enable students to use the restrictive relative clauses flexibly.3. Develop students speaking and cooperating abilities.4. Strengthen students great interest in grammar learning.【教学重难点】How to enable students to have a good understanding of the restrictive relative clauses, especially the uses of the relative words such as which, that, who, whom.【教学过程】Step1: 语法知识呈现定语从句（一）关系代词的用法在复合句中, 修饰名词或代词的从句叫定语从句。定语从句通常由关系代词或关系副词引导，说明事物的具体信息，从句位于被修饰词之后。被定语从句修饰的词叫先行词，引导定语从句的词叫关系词，关系词指代先行词，并在定语从句中充当成分。关系词有两种：关系代词who, whom ,whose, that, which, as和关系副词when, where, why。根据定语从句与先行词的关系，可将定语从句分为限制性定语从句和非限制性定语从句。一般说来，限制性定语从句是整个句子不可缺少的部分，如果省略会影响全句的主要意思，这种定语从句前面不用逗号隔开；而非限制性定语从句的作用是对所修饰的成分作进一步说明, 通常和主句用逗号隔开，将从句去掉后句子的意思仍然完整，译成汉语时，从句常单独译成一句话，除了that和why不能引导非限制性定语从句，其他关系词的用法和限制性定语从句关系词的用法相同。一、判断定语从句的关系代词的方法：如果名词或代词后有一个句子，并且该名词或代词在句子中充当成分，则该句子就是定语从句。主要按照以下三步来判断：1.找准先行词（定语从句前的名词或代词）。2.把先行词还原到定语从句中，看充当什么成分。3.根据先行词在定语从句中所充当的成分以及句意来选用适当的引导词。如果先行词在从句中作主语，宾语，定语，表语，则用关系代词，关系代词主要有who, whom ,whose, that, which, as。二、关系代词的基本用法指代关系代词以及在定语从句中充当的成分例句1.人who(主语、宾语)whom(宾语)that(主语、宾语)The man who/that is speaking at the meeting is a famous scientist.（作is speaking的主语）在会上讲话的人是一位著名的科学家。He who/that does not reach the Great Wall is not a true man.（作does not reach的主语）不到长城非好汉。This is the famous scientist (who/whom/that) we visited last week.（作visited的宾语）这就是我们上周拜访的那位著名科学家。2.物that(主语、宾语)which(主语、宾语)He finally worked out the problem which/ that puzzled him for a long time.（作puzzled的主语）他最后解出了这个令他困惑很久的问题。The fish (that/which) we bought yesterday were not fresh. （作bought的宾语）我们昨天买的鱼不新鲜。3.人的；物的whose(定语)They rushed over to help the man whose car broke down. （whose car=the mans car，作定语，修饰car）他们跑过去帮助那个汽车抛锚的人。There is a mountain whose top is always covered with snow.( whose top=the mountains top，作定语，修饰top)有一座山顶常年被雪覆盖的山。4.句子（在非限制性定语从句中）which(主语、宾语)as(主语、宾语)The weather turned out very good, which was more than we could expect.（which指代“天气最后晴朗起来”，作was的主语）天气最后晴朗起来，这是我们没有料到的。As everyone knows, China is a beautiful country with a long history.（As指代“中国是一个有着悠久历史的美丽国家”，作knows的宾语）每个人都知道，中国是一个有着悠久历史的美丽国家。三、关系代词易错点：1.关系代词的省略关系代词在定语从句中作主语时，不可省略；做宾语时，在限制性定语从句中可以省略，在非限制性定语从句中不可省略。Is he the man who /that wants to see you?（作wants的主语不可省略）他就是那个想见你的人吗？Hangzhou is a beautiful city(that/which)I always want to visit.（在限制性定语从句中作visit的宾语，可以省略）杭州是我总想参观的一个美丽城市。Hangzhou ,which I visited last week, is a beautiful city.（在非限制性定语从句中作visited的宾语，不可省略）杭州是一个美丽的城市，我上周去参观过。2.从句中代词的重复多余定语从句中的引导词指代先行词，并在从句中作成分，从句中不能再出现指代该先行词的代词。The book that I read it yesterday is very interesting.（）The book that I read yesterday is very interesting.（）我昨天读的那本书很有趣。This is the woman who I met her last time.（）This is the woman who I met last time.（）这就是我上次遇见的妇女。 3.关系代词和代词的误用定语从句的引导词要用关系代词，而不能用一般代词。This is the boy he told me a story yesterday.（）This is the boy who told me a story yesterday.（）这就是昨天给我讲故事的男孩。This is the boy his father is our headmaster.（）This is the boy whose father is our headmaster.（）这就是这个男孩，他的爸爸是我们的校长。4.what不引导定语从句定语从句中有关系代词that和which ，而没有what ，what 可以引导名词性从句。All that we need is a supply of oil. (that引导定语从句，修饰先行词all)What we need is a supply of oil. (what引导主语从句) 我们需要的是石油供应。5.that不引导非限制性定语从句（用逗号隔开）在非限制性定语从句，不能用关系代词that。如果指代“人”，用关系代词who/ whom，指代“物”，用关系代词which。The basketball star, who tried to make a comeback, attracted lots of attention. 这位打算复出的篮球明星引起了很多关注。Beijing, which is the capital of China, is a beautiful city. 中国的首都北京是座美丽的城市。He has become a doctor, which he wanted to be.他成为了一名医生，这是他以前一直梦想的。6.介词+which/whom先行词在从句中作介词宾语，若介词提前，指代物时，只能用which，不用that；指代人时，只能用whom，而不用who。介词不提前时，用that/which, who /whom都可以。I have the book about which you are talking. = I have the book (that/ which) you are talking about.我有你现在谈论的那本书。The man with whom I talked just now is from Beijing University.= The man (who/ whom/ that) I talked with just now is from Beijing University.刚才和我谈话的那个人是从北京大学来的。7.whose+n.= the+n+of which=of which+the+n.whose+n.可与the+n +of which互换，而且of which也可置于名词之前，名词之前必须有定冠词the。I live in the room whose window faces south.( whose window=the rooms window) I live in the room the window of which / of which the window faces south.( the window of which= the window of the room)我住在窗子朝南开的房间里。8. 定语从句中的主谓一致：关