中考了怎么练习英语作文

中考了怎么练习英语作文

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中考了怎么练习英语作文

中考了怎么练习英语作文【一】

1。 叙述的人称

英语的记叙文一般是以第一或第三人称的角度来叙述的。用第一称表示的是由叙述者亲眼所见、亲耳所闻的经历。它的优点在于能把故事的情节通过“我”来传达给读者,使人到真实可信,如身临其境。如:

The other day, I was driving along the street。 Suddenly, a car lost its control and ran directly towards me fast。 I was so frightened that I quickly turned to the left side。 But it was too late。 The car hit my bike and I fell off it。

用第三人称叙述,优点在于叙述者不受“我”活动范围以内的人和事物的限制,而是通过作者与读者之外的第三者,直接把故事中的情节展现在读者面前,文章的客观性很强。如:

Little Tom was going to school with an umbrella, for it was raining hard。 On the way, he saw an old woman walking in the rain with nothing to cover。 Tom went up to the old woman and wanted to share the umbrella with her, but he was too short。 What could he do? Then he had a good idea。

2。 动词的时态

在记叙文中,记和叙都离不开动词。所以动词出现率最高,且富于变化。记叙文中用得最多的是动词的过去的',这是英语记叙文区别于汉语记叙文的关键之处。英语写作的优美之处就在于这些动词时态的变化,正是这一点才使得所记、所叙有鲜活的动态感、鲜明的层次感和立体感。

3。 叙述的顺序

记叙一件事要有一定的顺序。无论是顺叙、倒叙、插叙还是补叙,都要让读者能弄清事情的来龙去脉。顺叙最容易操作,较容易给读者提供有关事情的空间和时间线索。但这种方法也容易使文章显得平铺直叙,读起来平淡乏味。倒叙、插叙、补叙等叙述方法能有效地提高文章的结构效果,让所叙之事跌宕起伏,使读者在阅读时思维产生较大的跳跃,从而为文章所吸引,深入其中。但这些方法如果使用不当,则容易弄巧成拙,使文章结构散乱,头绪不清,让读者不知所云。

4。 叙述的过渡

过渡在上下文中起着承上启下、融会贯通的作用。过渡往往用在地点转移或时间、事件转换以及由概括说明到具体叙述时。如:

In my summer holidays, I did a lot of things。 Apart form doing my homework, reading an English novel, watching TV and doing some housework, I went on a trip to Qingdao。 It is really a beautiful city。 There are many places of interest to see。 But what impressed me most was the sunrise。

The next morning I got up early。 I was very happy because it was a fine day。 By the time I got to the beach, the clouds on the horizon were turning red。 In a little while, a small part of the sun was gradually appearing。 The sun was very red, not shining。 It rose slowly。 At last it broke through the red clouds and jumped above the sea, just like a deep-red ball。 At the same time the clouds and the sea water became red and bright。

What a moving and unforgettable scene!

5。 叙述与对话

引用故事情节中主要人物的对话是记叙文提高表现力的一种好方法。适当地用直接引语代替间接的主观叙述,可以客观生动地反映人物的性格、品质和心理状态,使记叙生动、有趣,使文章内容更加充实、具体。试比较下面两段的叙述效果:

I was in the kitchen, and I was cooking something。 Suddenly I heard a loud noise from the front。 I thought maybe someone was knocking the door。 I asked who it was but I heard no reply。 After a while I saw my cat running across the parlor。 I realized it was the cat。 I felt released。

这本来应是一段故事性很强的文字,但经作者这么一写,就不那么吸引人了。原因是文中用的都是叙述模式,没有人物语言,把“悬念”给冲淡了。可作如下调整:

I was in the kitchen cooking something。 "Crash!" a loud noise came from the front。 Thinking someone was knocking at the door, I asked, "Who?" No reply。 After a while, I saw my cat running across the parlor。 "It's you。" I said, quite released。

中考了怎么练习英语作文【二】

非谓语动词系列训练(二)

一:在句子意思不变的情况下用分词或不定式改写下列句子:

1.When he saw from the top of the mountain, he viewed a beautiful city.

-----___________from the top of the mountain, he viewed a beautiful city.(用分词

2.When it was seen from the of the mountain, the city looks like a garden. (用分词 ------_____________from the of the mountain, the city looks like a garden. city. (用分词

3.When he was asked why he went there, he said he was sent there to be trained for a space flight.

-------When ________ why he went there, he said he was sent there to be trained for a space flight. (用分词

4. Do you know the boy who knows Japanese?

----- Do you know the boy ___________ Japanese? (用分词

5. Do you know the boy who is called Tom.

---- Do you know the boy ________Tom.- (用分词

6. This is the man who organized the activity.

This is the man________________ the activity. (用分词

7. He followed his students and came in.

------ He came in, ____________ his students(用分词

8. He came in and was followed by his students

----- He came in ,____________by his students(用分词

9.The woman who was dressed in a blue skirt delivered a speech to us.

---- The woman _____________ in a blue skirt delivered a speech to us. (用分词

10. Because he is a physicist, he could well explained how to do the research.

---- _______ a physicist, he could well explained how to do the research. (用分词

11. He was born on the 18th of January, 1979 in Taiwan, and he was raised by his mother and was shy and quiet during his childhood.

----- ____________on the 18th of January, 1979 in Taiwan, and he was raised by his mother and was shy and quiet during his childhood. (用分词

12. The flowers his friend gave him will die unless it is watered every day.

---The flowers his friend gave him will die unless ____________ every day. (用分词

13.When we were walking dogs, we came across a famous professor.

------ When ____________ dogs, we came across a famous professor. (用分词

14. He donated over 10 billion dollars in order that he could sponsor education, culture, sports, and public welfare in the earth-stricken area.

----- He donated over 10 billion dollars _____________education, culture, sports, and public welfare in the earth-stricken area.(用不定式

15 After he had finished his homework, he played the piano.

----- ____________ his homework, he played the piano.

16. After the bridge had been completed, it went through a hard time because of the bad weather.

----______________________, it went through a hard time because of the bad weather.

17 It is said that Bell invented the telephone.

18. Bell is said __________ the telephone. (用不定式

19. I don’t decide what I should do.

I don’t decide what__________(用不定式

20. It happened that he had been invited

---- He happened _____________

21.He was so young that he could not go to school. He was too young __________ to school.

22. When the test was finished, we began our holiday.

----- The test __________, we began our holiday.(用独立主格结构

23. As time goes by ,he becoms aware of it.

With time ________ by, he becomes aware of the significant of it.

24. The moon, which travels round the earth once every month, is a natural satellite of the earth.

---- The moon, ___________ round the earth once every month, is a natural satellite of the earth.

25. Though he had been told several times, he didn’t understand me.

-----_______ several times, he didn’t understand me.

26. After the problem was solved,he took a rest.

----With the problem ____________, he took a rest.

27. If time permits, we will

28.He lay there, his hand clenched, his eyes looking straight up.

---He lay there, his hand_______, his eyes looking straight up

29.I once read a book called Man, Woman and Child, which enabled me to understand the love in a family.

------I once read a book called Man, Woman and Child, ______________ me to understand the love in a family. (用分词

30.There are many places of interest, among which is the Yunji mountain,whose scenery is very beautiful, which attracts lots of tourists from different places every year.

------There are many places of interest, among which is the Yunji mountain,whose scenery is very beautiful, ____________ lots of tourists from different places every year. (用分词

二:非谓语动词完成句子练习

there was no doctor available. (only

, playing cards at home or taking a walk in the park? (spend

. (think

包括三名儿童). (child

5. 根据他的话判断), he did well in his exam. (judge

the Tang Dynasty. (date

7. This is an article (由五部分组成)five parts. (consist

five parts.(make

as soon as possible. (solve

bored a lot of fans to death. (concern

, l cannot object to your marriage. (concern

子)at school? (keep)

(躲在木箱里)behind the door. (hide

,we had to walk home last night. (be.

in the broad daylight yesterday. (rob

(满是脚印). (mark

(石油价格上涨), the economy of that country is slowing down. (go

18. When the national flag is being hoisted, all the students stand at attention, . (fix

him, I decided to write again. (hear

20. He doesn’t seem to mind by others. (make

next week is of great importance. (hold

is very important. (hold

is of great importance. (hold

the Third World. (belong

(致力于研究), the professor paid little attention to his surroundings. (devote

in the morning. (come

(为了确保那孩子尽快康复),five doctors took turns looking after him day and night. (ensure

,the old man struggled to his feet. (help

, the parents were taken to the dining room. (show)

(.support)

. (drop)

, I am not familiar with this kill. (tell

(为了不被注意)by others . (notice

三:合并下列句子

1. The annual school sports meeting was held yesterday. It presented a marvelous opening ceremony.

__________________________________________________________________________________________________________________________________

2. After the opening ceremony, we sat in the base of our class. We waited patiently for the beginning of the race.

_____________________________________________________________________________________________________________________

3. Some of my classmates work very hard, and they hope to fulfill their dream. __________________________________________________________________________________________________________________________________

4..My friend Christine took part in the 800-meter race. She had received training many times, so she kept calm before the race. After 400 meters, though she looked tired, she still tried her best to run. We screamed and beat the drum when we saw she passed by. She won the medal, and we were proud of it. (把短文中的从句或并列句改成非谓语动词

____________________________________________________________________________________________________________________________________________________________________________________________________________________________

______________________________________________________________________________________________________________

四:语篇填空 用所给动词的适当形式填空。(一)

Freud was one of the first scientists [1]_________(make)serious research of the mind. The mind is the collection of activities [2]_________(base) in the brain that involve how we act, think, feel and reason. He used long talks with patients and the study of dreams [3]___________(search) for the causes of mental and emotional problems. He also tried hypnosis(催眠. He wanted to see if [4]________(put)patients into a sleep-like condition would help ease

[5]________(trouble) minds. In most cases he found the effects only temporary. Freud worked hard, although what he did might sound easy. His method involved [6]________ (sit with his patients and [7]________(listen)to them talk. He had them [8]________(talk)about whatever they were thinking. All ideas, thoughts and anything that entered their mind had to

[9]___________(express). There could be no[10]________(hold)back because of fear or guilt. 基础写作 :最近,你就读的学校——广东实验中学高中部将举办开放日。 你将作为学校的

学生代表向前来参观的英语老师介绍高中校区的基本情况,请准备好你的解说词,文章的开头和结尾已为你写好。(学会用非谓语动词表达)

?位置交通:位于广州市西部,荔湾区;出行便利,步行到地铁站约10分钟。 ?学校历史:逾120年的悠久历史;现高中校区于2004年 竣工并投入使用。 ?校园环境:占地面积约125,000平方米;植物繁茂,绿树成荫,环境优美。 ?校园设施:课室宽敞明亮,配备齐全;拥有标准运动 设施,

其中综合体育馆可用于举办比赛、会议和典礼。

?师生情况:目前学生约3000人,教师约200人;全体师生正在

为学校更美好的明天共同奋斗。

?【写作要求】

?只能用5个句子表达全部内容。?【评分标准】 ?句子结构准确,信息内容完整,篇章结构连贯。

Good morning, teachers! Welcome to Guangdong Experimental High School!.....

__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

非谓语动词练习答案

1.Seeing 2.Seen (原句有误,请改成When it was seen from the top of the mountain,the city is beautiful (用分词 3. asked 4. knowing 5. called 6. organizing 7. following 8. followed 9. dressed 10. Being 11. Born 12. watered 13. walking 14. to sponsor 15. Having finished 16. Having been completed 17 18.. to have invented

19.to do 20. to have been invited 21. to go 22 finished 23. going 24. travelling 25. Having been toldTold 26. solved 27.permitting 28. clenched 29.enabling 30. attracting

二:非谓语动词完成句子练习

Keys:

1. only to be told (that 2. to spend your spare/free time

3. thinking about 4. including three children/ three children included

5. Judging from / by his words/what he said

6. dating back to/from (which dates back to/from

7. consisting of / which consists of

8. made up of/which is made up of 9. to solve the problem

10. concerning the football match 11. As/So far as I am concerned

12. (in keeping five children 13. hidden in a wooden box

14. There being no bus 15. to have been robbed

16. Seen from the top of 17. Seeing from the top of

18. To see 19. marked with footprints

20. the price of oil going up 21. fixed on/upon the national flag

22. with (both his hands tied 23. Not having heard from

24. (his being made fun of 25. to be held

中考了怎么练习英语作文【三】

按要求改写句子知识点梳理

一、概述

按要求改写句子主要考查学生对句子结构的掌握以及用不同句型表达同一意思的能力。考查所涉及到的句子类型有一般疑问句、否定句、反意疑问句、选择疑问句、对划线部分提问、感叹句、保持原句意思、合并成一句、简单句和复合句之间的互换以及改为被动语态等。

二、解题时需注意的几个要点

1、时态:不同的时态相对应的助动词

一般现在时:谓语动词用原形(主语为第三人称单数时,动词加s或es,变否定句、疑问句时助动词为do或does)

一般过去时:谓语动词用过去式,变否定句、疑问句时助动词为did.

现在完成时:助动词have/has+动词的过去分词

过去完成时:助动词had+动词的过去分词

一般将来时:will/be going to +动词原形

过去将来时:would/was or were going to +动词原形

现在进行时:am/is/are+动词的现在分词

过去进行时:was/were+动词的现在分词

2、语态:主动语态变为被动语态的谓语结构

一般现在时:am/is/are+动词的过去分词

一般过去时:was/were+动词的过去分词

一般将来时:will be+动词的过去分词

情态动词:can/may/must/need等情态动词+be++动词的过去分词

3、改反意疑问句时注意hardly, never, seldom, few, little, no等词表达的是否定意义,变反意疑问句时用肯定形式。

4、在合并句子时,有些连词如not only…but also…, neither…nor…, either…or…是就近原则,连接两个主语时动词形式取决于与动词邻近的主语。而both…and…连接两个主语时,主语是复数。

5、简单句和复合句之间的互换常见的有:带有疑问词的宾语从句改为特殊疑问词+to+动词原形的不定式;结果状语从句so…that…改为enough to或too…to…的简单句。

6、保持原句意思改写句子时注意时态不变。

三、习题

练习一

1. We do our homework every evening. (改为否定句)

We _________ ________ our homework every evening. 对划线部分提问

________ ________ do they have a class meeting?

3. She could hardly understand this passage. (改为反意疑问句

She could hardly understand this passage, _________ __________?

4.The manager told him how to get useful information. (改为否定句

The manager _________ _________ him how to get useful information.

5. Tom’s sister can speak English and Japanese very well. (改为反意疑问句

Tom’s sister can speak English and Japanese very well, _________ _________?

对划线部分提问

_________ _________ he live twenty years ago?

7. Sam does some cleaning in the morning. (改为否定句

Sam _________ do _________ cleaning in the morning.

对划线部分提问

_________ _________ have the students worked on the survey?

9. Your father used to ride a bike. (改成反意问句)

Your father used to ride a bike, _______ ________? (对划线提问)

__________ ___________ the population of Germany?

11. Mr. Wang washes his car once a month. (改为一般疑问句)

Mr. Wang (对划线部分提问

will Susan come back from Athens?

13. My friends lost their way when they were traveling in Hong Kong. (改为一般疑问句

________ your friends ________ their way when they were traveling in Hong Kong?

14. 对划线部分提问

________ ________ has Yao Ming been in the Rocket Team?

15. She put the digital camera on the bed just now. (改为否定句

She _________ _________ the digital camera on the bed just now.

16. Mark's flown to Hainan Island for winter holidays. (改为反意疑问句

Mark's flown to Hainan Island for winter holidays, _________ _________?

(专辑. (划线部分提问

_________ did Super Girl Zhou Bichang _________ to Vienna?

18. I’ve already saved enough money to buy a new car. (改为否定句

I ________ saved enough money to buy a car ________.

19. Lily used to have long straight hair. (改为反意疑问句

Lily used to have long straight hair, ________ ________?

20. He has already been there .(改为一般疑问句

__________ he been there __________?

21.They decided that they wouldn't have the picnic because of the bad weather. (改为简单句

They decided __________ _________ have the picnic because of the bad

weather.

22. The English people hardly ever shake hands between the strangers .( 改为反意疑问句

The English people hardly ever shake hands between the strangers, __________ __________?

23. They grew some sunflowers in their garden last year.(改为否定句)

They __________ __________ any sunflowers in their garden last year.

24. Jane drinks milk every morning.(改为一般疑问句)

_________ Jane ___________ milk every morning? (就划线部分提问)

___________ map ___________ to Class 4?

26. You can choose only one of the two: a mini-TV or a DVD player. (改为选择疑问句

you want a mini-TV a DVD player?

27. That detective film is so amazing. (改为感叹句)

___________ ___________ amazing detective film!

28. He has some money left.(改成否定句)

He money left.

29. (划线部分提问)

do the members of the film society meet?

30. His mother knew why the little boy was unhappy all day. (改为一般疑问句

_______ his mother _______ why the boy was unhappy all day?

31. He looks very funny with that hat on. (改为感叹句

_______ _______ he looks with that hat on!. 对划线部分提问

_______ _______ they build this factory?

33. I have already finished the test paper.(改为否定句)

I ________ finished the test paper ________.

34. Johnson denied cheating in the competition.(改为反意疑问句)

Johnson denied cheating in the competition, ________ ________? (对划线部分提问) ________ ________ the story need to be funny?

36. Sam does some cleaning in the morning. (改为否定句

Sam _________ do _________ cleaning in the morning.

对划线部分提问 _________ _________ have the students worked on the survey?

38. (对划线部分提问) _________ _________ has he been a top fashion designer?

39. 对划线部分提问

________ ________ will they move into the new school?

40. to go to the People’s Square by underground. (对划线部分提问

________ _______ did it take you to go to the People’s Square by underground?

练习二:

1. Gold is less valuable than diamond. (保持句意不变

Gold is ________ ________ valuable as diamond.

2. He told the children to go and watch his tank of Ghost fish. (改为被动语态 The children ________ ________ to go and watch his tank of Ghost fish.

3. Unless I have a quiet room, I cannot do any work. (保持句意不变)

I cannot do any work ________ I _________ have a quiet room.

4. The manager arrived here a few minutes ago. (保持句意不变)

The manager has _________here ________ a few minutes.

5. They will send him to work in Japan for one year. (改为被动语态

He will ________ _________ to work in Japan for one year.

6. The words on the notice board are very small. I can’t see them clearly.(保持句子原意

The words on the notice board are small I can’t see them

clearly.

7. We can solve the problems with the help of the teacher. (改为被动语态 The problems can _________ _________ with the help of the teacher.

8. We can’t finish the work in such a short time. (保持原句意思

It’s _________ _________ us to finish the work in such a short time.

9. We must keep the noise under 50 dbs.(分贝(改成被动语态)

The noise must ________ _______ under 50 dbs here.

10. Mike doesn’t like classical music. Billy doesn’t either. (合并成一句) _________ Mike nor Billy __________ classical music.

11. The room is so dirty that we can’t live in it.(保持句意不变)

The room isn’t __________ _________ for us to live in.

12. No one knows when we will start tomorrow. (保持原句意思)

No one knows start tomorrow.

13. The Smiths will invite the professor to take part in the party. (改成被动语态 to take part in the party by the Smiths.

14. If you are not brave, you’ll lose your last chance.(保持原句意思)

you are ’ll lose your last chance.

15. They store much information in the computer. (改成被动语态

Much information ________ ________ in the computer.

16. Don’t throw rubbish here and there. Our teacher said to us. (合并为一句

Our teacher told us ________ ________ throw rubbish here and there.

17. If John doesn’t apologize for what he did, I will tell the teacher about his bad behavior.

(保持原句意思)

_______ John _______ for what he did, I will tell the teacher about his bad behavior.

18. I don't know where we can grow vegetables in the city. (改为简单句 I don't know _________ _________ grow vegetables in the city.

19. People used to enjoy themselves chatting on MSN when it worked well. (保持句意基本不变

People used to _________ a lot of _________ chatting on MSN when it worked well.

20. If you don’t improve your handwriting, you will lose marks in the exam. (合成同义句

You will lose marks in the exam ________ you ________ your handwriting.

21. To go fishing is fun. (句意不变 )

_____ is fun _____ ______ fishing.

22. Dick was so short that he couldn’t touch the top of the bookshelf.(保持句意基本不变)

Dick wasn’t __________ __________ to reach the top of the bookshelf.

23. “Can I borrow your bike for a while or not?”( 保持句意基本不变)

Tom asked his sister __________ he __________ borrow her bike or not for a while.

24. The couple couldn’t decide which flat they should choose at first. (保持原句意

思)

The couple couldn’t decide which flat at first.

25. Meaningless information is difficult for the little boy to remember. (保持原句意思)

is difficult for the little boy remember meaningless information.

26. People throw away millions of plastic bags in our city every day. (改成被动语态)

Millions of plastic bags away in our city.

27. She was so careless that she couldn’t find the mistakes in her test paper. (保持句意基本不变

She was _______ _______ to find the mistakes in her test paper.

28. We will hold the next Olympic Games in Beijing in 2008.(改为被动语态)

The next Olympic Games will _______ _______ in Beijing in 2008.

29. The elderly man pushed the birds into the river.(改为被动语态)

The birds ________ ________ into the river by the elderly man.

30. Dolphins are so clever that they can follow the instructions.(保持句意基本不变) Dolphins are ________ ________ to follow the instructions.

31. We can’t finish the work in such a short time. (保持原句意思

It’s _________ _________ us to finish the work in such a short time.

32. They invited the astronaut and his wife to the party on Christmas Eve.(改为被动语态

The astronaut and his wife _________ _________ to the party on Christmas Eve.

33. The little girl didn’t go to bed unless the grandmother told her a story. (保持句意基本不变

The little girl didn’t go to bed _________ the grandmother _________ tell her a story.

34. The plane is so big that it can carry 300 passengers at one time. (改为简单句)

The plane is big _________ _________ carry 300 passengers at one time.

35. Did they know the answer to the question? Ididn’t know… (合并为一句 I didn’t know ________ they had ________ the answer to the question.

Keys

练习一

1. don’t do 2. How often 3.could she 4.didn’t tell 5.can’t she

6.where did 7.doesn’t any 8.How long 9.didn’t he 10.What is

中考了怎么练习英语作文【四】

??年级英语暑假改写句子的练习题

1. It is fun at school.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

2.I like grapes.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

3. Miss Green is a good English teacher.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

4. Norman likes maths.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

5. Jim is watching TV.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

6.There are so many animals.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

7.I can hear something in the next room.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

8. I’ve got the letter“n”.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

9. MMike has got a picture of Shanghai.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

10.There’s a big playroom in our school.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

11. They have got some bananas.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

12. Tom and Jim are watching a match.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

13. I want some carnations for my mother.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

14. Those are roses.

改成否定句__________________________________________

改成一般疑问句______________________________________

肯定回答_____________________________________________

否定回答_____________________________________________

中考了怎么练习英语作文【五】

山本茂是日本警察科学研究所的一名法医,但他研究植物血型纯属偶然。一天,有个名叫大岛川冈的人驱车经过千叶县城郊时,不慎撞伤了一名儿童。几天之后,警察追踪到他的车。经检查,汽车的前轮上不仅粘有那名儿童的O型血,而且还带有B型、AB型两种血迹。于是,警局指控大岛川冈撞过三个人。但面对证据,大岛川冈只肯承认撞伤过一名儿童,对另两项指控坚决予以否认。另一方面,警方也不能提供确凿证据,法院一时难以裁决。

与此案相隔不久,一名妇女夜间死于床头。法医化验她的血迹为O型,而枕头上的血型却是AB型,于是被疑为他***。除此之外,并无凶手作案的任何证据。这时有人半开玩笑地说:“莫非枕头内的荞麦皮属AB型?”谁知这个谜一般的提示,给了一筹莫展中的山本茂一个极大的启迪。他决定取荞麦皮进行化验,最后发现荞麦皮果真属AB型,这使山本茂如获至宝,欣喜若狂。他立即对发岛川冈的汽车重新取样验证,结果发现车轮上的3种血型中,有两种属于植物。至此,撞人案才水落石出。

从那以后,山本茂一直潜心于植物血型的研究。据他对150种蔬菜、水果以及500种被子植物和裸子植物的种子的化验测定,证实了“植物也有血型”这一结论的普遍性。例如,桃叶等19种植物为A型血型;苹果、草莓、西瓜、海带等77种植物为O型血型;枝状水藻等54种植物为B型血型;李子、桃子等400种植物属于AB型血型。据目前的'研究可以肯定,植物血型与热泪血型是类同的。科学家还发现,同一种植物还可以有不同的血型,比如枫叶为黄色时,其血型为AB型,但秋天枫叶红了的时候,它的血型又变成了O型。

植物本无血液,何以有血型之分呢?根据现代分子生物学的基础理论可知,人类血型指的是血液中红血球细胞膜表面分子结构的类型。而植物体内相应存在一类带有糖基的蛋白质或多糖链,或称凝集素。有的植物的糖基恰好同人类体内的血型糖基相似;如果以人体抗血清进行鉴定血型的反应,植物体内的糖基也会跟人体抗血清发生反应,从而显示出植物糖基有相似于人的血型。为了弄清血型植物的基本作用,科学家对植物界作了深入研究后得出的结论是:如果植物糖基合成达到一定的长度,在它的尖端就会形成血型物质,然后合成就停止了。血型物质的黏性大,似乎还担负着保护植物体的作用。

科学家指出,植物血型是一门十分深奥的学问,其复杂程度绝不亚于动物血型,而且它很有可能成为人类社会的天然血库。换句话说,科学家研究植物血型的最终目标,就是要让植物为人类提供血源,使自然界繁茂的植物成为浩瀚的天然血库。

16、给下面加点的字注音。

确凿( ) 一筹( )莫展 浩瀚( )

17、指出下列句子使用的说明方法。

(1)据他对150种蔬菜、水果以及500种被子植物和裸子植物的种子的化验测定,证实了“植物也有血型”这一结论的普遍性。

(2)例如:例如,桃叶等19种植物为A型血型;苹果、草莓、西瓜、海带等77种植物为O型血型。

18、植物本无血液,何以有血型之分呢?

19、科学家研究植物血型有什么目标?

20、作者举大岛川冈和妇女的事例有什么作用?

中考了怎么练习英语作文【六】

Therearesomecherriesinthebasket.(一般疑问句,否定回答划线部分提问Kittylikesthebluedress.(用thepinkdress改为选择疑问句Don`tplaywithfires.(换一种说法

Joelikesreading.Dannylikesreadingtoo.(把两句连成一句Pleaseeatsomecakesandbiscuits.(改为否定句划线部分提问Thereissomewaterintheglass.(划线部分提问划线部分提问Whatdayistoday?

What`sthedatetoday?

Whatdoyouusuallydoafterdinner?

Whichpearsdoyouwant,thegreenonesortheyellownoes?Whichwesternholidaydoyoulikebest?Whenisit?

WhatdoyoudoattheLanternFestival?

5B2

Thosebooksareours.(同义句划线部分提问划线部分提问

ThosecrayonsareDanny`s.(.(用Alice改为选择疑问句Arethesetheirschoolbags?(单数句划线部分提问

Theyridetheirbicyclestothepark.(用May改写

Thecocooniswhite.(用browng改为选择问句划线部分提问Heisfouryearsold.(改为一般过去时

Iwasathomeyesterdayevening.(改为一般疑问句

Thecaterpillarslikeeatingleaves.(改为单数句划线部分提问划线部分提问

WhatdoyoueatattheMid-autumnFestival?(根据实际情况回答

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