七年级英语 下册下册Unit 3-4的语法归纳

1、.七年级英语 人教版下册下册Unit 3-4的语法归纳一、学习目的掌握下册Units 3-4的语法内容。二、重点、难点重点：1. how引导的特殊疑问句；2. 祈使句的用法；3. 情态动词have to, must。难点：祈使句的用法。【语法学习】一、how引导的特殊疑问句【用法1】how引导的特殊疑问句，可用来询问做某事的方式或方法，也可用来询问某人或某物的状况。【用法2】how可与其他词连用，来引导特殊疑问句。 how old 多大，提问年龄。【例句】How old is your sister? 你的妹妹多大了？ how many 多少，提问可数名词的量。【例句】How many ban

2、anas do you want? 你想要多少香蕉? how much 多少，提问不可数名词的量。 多少钱；提问价格。【例句】How much water is there in the bottle? 瓶子里有多少水？How much is the sweater? 这件毛衣多少钱？ how long 多长时间，提问一段时间。 多长，提问物体的长度。【例句】How long does it take you to get home? 你到家要花费多长时间？How long is the classroom? 这教室多长？ how far 多远，提问间隔 。【例句】How far is the

3、 park from here? 公园离这儿多远？【拓展】 how soon 多快。【例句】How soon will he be back? 他多快回来？ how often 多久一次，提问频率。【例句】How often do you go to the movie? 你多久去看一次电影？【考题链接】1. _ is it to the train station? About six kilometers.A. How long B. How far C. How much D. How often答案：B思路分析：根据答语“大约六公里可知问句询问间隔 ，故排除A, C, D三项。2. _

4、 do you live here?For about five months.A. How much B. How often C. How long D. How far答案：C思路分析：根据答语“大约五个月可知问句提问一段时间，应选C项。3. _ are the socks?Theyre 10 yuan.A. How old B. How much C. How soon D. How many答案：B思路分析：根据答语“它们10元可知问句提问价格，应选B项。对画线部分提问1. I go hiking twice a week._ _ do you go hiking?2. It tak

5、es me 15 minutes to walk to school._ _ _ it _ you to walk to school? 3. Its three miles from my home to school._ _ is it from your home to school?4. I go to school by car._ _ you go to school?5. I sleep nine hours every night._ _ _ do you sleep every night?6. His son is 11 years old._ _ is his son?7

6、. The boy will finish his homework in 2 hours. _ _ will the boy finish his homework?8. I want two glasses of milk._ _ milk do you want?9. I think the book is interesting. _ do you _ the book?10. My skirt is 20 dollars. _ _ is your skirt?答案：1. How often 2. How long does; take 3. How far 4. How do 5.

7、How many hours 6. How old 7. How soon 8. How much 9. How; like 10. How much二、祈使句的用法1. 定义用来表示恳求、命令、建议、号召、警告等的句子。说话的对象大多为第二人称you，且常被省略。句末用感慨号或句号，读时用降调。为了表示客气，常用please一词。放在句首时，其后不加逗号；放在句末时，其前通常加逗号。2. 构成祈使句分为肯定祈使句和否认祈使句。1 肯定祈使句的构成： Do型，即以行为动词原形开头。【例句】Stand up, please! 请起立！ Be型，即以动词be开头。【例句】Be quiet plea

8、se! 请安静！ Let型，即以let开头。【例句】Lets play basketball. 让咱们去打篮球吧。【考题链接】1. Please _ the blackboard.A. look B. look at C. to look D. to look at答案：B思路分析：本句是一个祈使句，动词用原形。look是不及物动词，后接宾语时要先接介词at，故B项正确。2. Let Lily _ piano.A. play B. to play C. to play the D. play the答案：D思路分析：阅读题干，piano是乐器“钢琴，故“弹钢琴用play the piano；l

9、et sb.后接动词原形，应选D项。2 否认祈使句的构成： Do型和Be型的否认式，在动词前加dont或never。【例句】Dont come in. 不要进来。Never be angry. 绝不生气。 Let型的有两种否认形式：在let前加dont 或在let sb. 后加not。【例句】Dont let them cry. = Let them not cry. 不要让他们哭。Let me not go there. = Dont let me go there. 不要让我去那儿。No +v.-ing形式/名词，用于警示人们不要做某事。No swimming! 制止游泳！No photo

10、s! 制止拍照！【考题链接】1. _ late for school.A. Not be B. Not is C. Dont be D. Dont is答案：C思路分析：阅读题干和选项可知此题考察否认祈使句。开头用Dont，后接动词原形，故C项正确。句意为“上学不要迟到。2. _ smoking!A. Not B. Dont C. No D. Doesnt答案：C思路分析：smoking是动词的-ing形式，故其前用No。句意为“制止吸烟！。3. 答语祈使句的动作通常是将来发生的动作，所以答复祈使句时，一般用will或wont。【例句】Please pass me that book. 请把那

11、本书递给我。OK, I will. 可以。【注意】在答复具有否认意义的祈使句时，要注意形式一致和意义相反。即：yes与will；no与wont要一致；yes意为“不；no意为“是。【例句】Dont go out. Its raining hard. 不要出去了。天正下着大雨。Yes, I will. Lily is waiting for me. 不，我要去。莉莉在等我呢。【考题链接】Peter, dont step on the grass. _. A. It doesnt matter B. I cant do it C. Dont worry D. Sorry, I wont do it

12、 again答案：D思路分析：阅读题干可知是否认祈使句“不要践踏草地，其答语应选D项“对不起，我不会再那样做了。其他三项不合句意。4. 注意祈使句和陈述句的连用祈使句与陈述句连用，有两种形式：1祈使句+ and/ then + 陈述句，二者之间表示一种顺承关系。【例句】Study hard, and you can get good grades. 努力学习，你就会获得好成绩。2祈使句+ or +陈述句，二者之间表示一种否认条件关系。【例句】Hurry up, or well be late. 快点，否那么我们会迟到的。【考题链接】Hurry up, _ you will miss the e

13、arly bus.A. or B. and C. so D. but答案：A思路分析：阅读各选项可知A项意为“或者；否那么；B项意为“和，表示并列关系或顺承关系；C项意为“所以，表示因果关系；D项意为“但是，表示转折关系。根据句意“快点和“你会耽误早班车可知用or，意为“否那么。句型转换1. You must come here early tomorrow. 改为祈使句_ here early tomorrow!2. Look at the picture! 改为否认句_ _ at the picture!3. Let her help you. 改为否认句_ _her help you.4

14、. You cant be late next time. 改为祈使句_ _ late next time.5. You can drink and eat in the dining hall. 改为否认祈使句_ drink _ eat in the dining hall.答案：1. Come 2. Dont look 3. Dont let 4. Dont be 5. Dont; or 三、情态动词have to, must1. have to意为“不得不，强调客观需要，能用于多种时态。本身有第三人称单数形式has to。【例句】My brother is ill. I have to

15、look after him at home. 我弟弟生病了。我不得不在家照看他。【考点1】一般如今时态中，have to 的否认句要借助助动词dont / doesnt，再加have to。【例句】You dont have to come here so early. 你不必那么早来这儿。Lucy doesnt have to wear school uniforms. 露西不必穿校服。【考点2】一般如今时态中，have to的一般疑问句要借助于助动词do/ does放在开头，后接have to。【例句】Does he have to wear a hat? 他必须戴帽子吗？【考点3】一般

16、如今时态中，特殊疑问句是：特殊疑问词+ do/ does+主语+have to +其他？【例句】What does he have to do? 他必须做什么？【考题链接】Its too late. We _ go home.A. can B. have to C. may D. must答案：B思路分析：根据“天太晚了可知“我们不得不回家，是客观上的必须，应选B项。2. must意为“必须；应当，表示义务、命令或必要。强调主观看法，没有时态变化。否认式mustnt表示“制止，严禁。【例句】He must work today. 今天他必须工作。You mustnt take the book

17、 away from the library. 你不可以把这本书带出图书馆。假如将书带出图书馆将违背相关法律法规。【考点4】以must开头的一般疑问句，简单肯定答复用must，简单否认答复用neednt或dont have to。neednt 相当于dont have to，意为“不必。【例句】Must I do the dishes today? 我今天必须洗餐具吗？Yes, you must. / No, you neednt/ dont have to. 是的，必须。/ 不，你不必。【考题链接】1. May I go to the cinema, Mom?Certainly. But y

18、ou _ be back by 11 oclock.A. can B. may C. must D. need答案：C思路分析：根据答语“当然可以了和转折连词but可知后句句意为“你必须11点以前回来。应选项C正确。can意为“能；会；可以；may意为“可以；need意为“需要；有必要。2. Dad, must I finish my homework today?No, you _. You may do it tomorrow.A. neednt B. mustnt C. dont D. wont答案：A思路分析：以must开头的一般疑问句，其简单否认答复用neednt或dont have

19、 to。阅读各选项可知A项正确。句型转换1. He has to eat in the dining hall. 改为否认句He _ _ to eat in the dining hall.2. We must be on time. 改为一般疑问句_ we _ on time?3. Bill has to listen to the music outside. 改为一般疑问句_ Bill _ to listen to the music outside?4. Must they follow the rules? 作否认答复_, they _.5. The students have to read books in the morning. 对画线部分提问_ _ the students _ to read books?答