Unit 2 Saving the earth topic 2知识点讲义仁爱科普版英语九年级上册

unit 2 topic 2
1. While I was walking down the street，I couldn't see anything.
when 与 while 的区分：
(1)while=when+延续性动词“当……时”。
注意：when 后可以跟瞬间动词，而while 却不能。此时when=and at this time，“就在此时”。
He was having supper when (=and at this time)someone knocked at the door.他正在吃晚餐，这时有人敲门了。
(2)while 和……同时(主从句都用过去进行时态)。
(3)while 作“然而”讲(表对比)。
When/While he was having supper，someone knocked at the door.当他正在吃晚餐时，有人敲门了。
My mother was cooking while my father was reading a newspaper.我爸爸在看报时，我妈妈在做饭。
He is an engineer while I am a teacher. 他是一名工程师，而我是一名老师。
1.He was listening to music _____________ he was riding his bike.
2.I was waiting at the lights _____________ I saw the boy fall off his bike.
3.I was walking in the street _____________ I saw the accident happen.
4.The driver was talking on his mobile phone _____________ he was driving.
2.People cut down too many trees. As a result, a lot of rich land changed into desert.
turn ...into...= change...into... 变成
Water can turn into ice. = Water can change into ice.
Little things can turn into wonderful things. 小事情可以变成美好的事情。
( ) 1.She made one big mistake, and , she lost her job last month.
A. of course B.as a result C.at last D.as first
2. 约翰上班经常迟到，结果丢掉了工作。
John was often late for work. ______________ ______________ ______________, he lost his job.
( ) 3. The children want to change iron _____ gold. But it’s impossible.
A. to B. into C. in D. in to
4.在那个故事中，一条小鱼变成了一位美丽的姑娘。
A small fish_________ _________ a beautiful girl in that story.
3. Trees can stop the wind from blowing the earth away.
Stop ...from (doing) sth. = prevent ... from (doing) sth. = keep ...(away) from...(doing) sth.
Parents stop their children from playing games.
=Parents prevent their children from playing games.
=Parents keep their children away from playing games.
1. —Look the factory is pouring waste water into the river.
—That’s terrible ! Why not ___them from ____that
prevent; to do B. stop; doing C. to keep; to D. to stop; to do
( )2.The Green Great Wall can stop the wind_____ blowing the earth away.
A.to B.from C.of D.with
( )3.The cleaners must keep the street _____.
A.from getting dirty B.to dirty C.to get dirty D.getting dirty
4.And a lot of water can be saved by forests.
save 动词，意为“储存，保留，保存”。
(1)save sb. sth. =save sth. for sb. 为某人保留……
(2)save 节省，节约，避免(金钱、时间、精力等的)浪费。
(3)save 救，拯救，挽救。save one's life 挽救某人的生命。
1.We'll eat some now and save some for tomorrow.我们现在吃一些，留一些明天吃。
2.Will you save me a seat on the bus 请在公共汽车上给我留个座位好吗
3.We'll save a lot of time if we go by bus.我们要乘公共汽车去可以节省很多时间。
4.He saved his friend from drowning. 他救起了他那位溺水的朋友。
5. 树木的作用
Trees can stop the wind from blowing the earth away.
A lot of water can be saved by forests.
Trees can stop the water from washing the earth away.
Cutting down trees affects the weather so much.
Cutting down too many trees is harmful to human beings, animals and plants.(反过来说）
( )1.We must plant more trees after we _____ every year.
A.take away them B.take them away C.cut down them D.cut them down
6. Although there were sandstorms before,now we have built "The Green Wall".
让步状语从句，though引导状语从句，常和still连用，不可与but同时出现。
Though he is poor, he is happy.
Although she is old, she is still healthy.
Although it is raining, they are still working in the field.
( )1. _____Liang Li is very busy,she always helps others.
A.But B.And C.Although D.Because
7.Humans have come to realize the importance of protecting animals. 人类已经开始意识到保护动物的重要性。
come to do sth. 尤指随时间或经历的增长，开始对某人或某物产生某种感情或想法。
Living in the countryside, I came to love the peace and quiet.住在乡下，我慢慢爱上了那份宁静。
He came to hate his job because of the constant pressure.由于持续的压力，他渐渐开始讨厌自己的工作了。
8. It says that the condition of the air has become better than before.
Sth.+ says that ...，此句型的主语是事或物，say 表示用“数字、文字”说明信息。
It says “Happy New Year!” on the card.
同结构：It is said that... 据说……，It is reported that... 据报道……，
It is well-known that... 众所周知……，It is believed that... 人们相信……
9.The government has done something useful to protect the environment.
Something/anything/everything/nothing + 形容词
I have something interesting to tell you.
The doctor examined her but could find nothing wrong.
somewhere warm 一些暖和的地方； nothing serious 没什么严重的
( )1. —Is there _____ in today’s newspaper
—Yes. Germany beat Argentina 1-0 to make history of winning World Cup in America.
A. anything new B. new anything
C. something new D. new something
2.用复合不定代词或不定副词填空：
1. I can't hear anything = I can hear .
2. There is on the floor. Please pick it up.
3. Did go to play basketball with you
4. I phoned you last night, but answered it.
5. Why don't you ask to help you
6. Could I get to drink
7. There's in the box. It's empty.
8. Maybe put my pencil away. I can't find it .
9. --- Do you have special to tell me today --- No, special.
10. --- Who is in still in your classroom --- (没有人).
10. None of us likes pollution.
none 可指人也可指物，作主语时，如和of 连用指不可数名词时，
谓语动词要用单数形式；指可数名词时，谓语动词用单、复数均可。
None of us likes/ like pollution.
None of them have/ has seen me before.
None of the bread belongs to me.
1 ）none 可与of 连用表示范围，而no one / nobody 及nothing 不可。
2 ）none 可用来回答How many / much…？的特殊疑问句；
而no one / nobody 及nothing 则分别用来回答Who…？和What…？
的特殊疑问句。如：
How many boys are there on the playground ---None.
What is in the box --- Nothing.
Who is in the room --- None / Nobody.
none of (三者及三者以上) +可数n复数+谓v单或复
none of (三者及三者以上) +不可数n+谓v单
none of (三者及三者以上) +代词复数+谓v单或复
( )1. I asked three people the way to the hospital, but _____ of them could help me.
A. everybody B. nobody C. none D. anybody
( )2.—How clean and tidy your school is! — Yes. _______ of us throw rubbish.
A. Nobody B. None C. No one D. Nothing
( )3.None of us _____ running, but we all like swimming.
A.likes B.like C.liking D.would like to
11. 保护环境的措施。
We shouldn’t leave rubbish here and there.
Don’t spit anywhere in public.
Don’t walk on grass or pick flowers.
Everyone should care for wild animals and plant more trees.
We should do everything we can to protect the environment.
I think we should make rules to change the situation. People who break the rules will be punished.
If we do our best to follow the rules , our school environment will improve.
12. but if everyone does his or her best to follow the rules, our school environment will improve.
If引导的条件状语从句，时态“主将从现”。
If you keep working hard, you ‘ll get a good result/grades.
If he comes, I will tell you.
make rules 制定规章 break/disobey rules 违反规则 follow/obey rules 遵守规则
13. Some things we have done are very good for the earth while others are bad.
(1)While作为并列连词,意思为“而,然而”,表前后意义上的对比或转折
Some people waste food while others haven't enough.
有些人浪费粮食,然而有些人却吃不饱。
He is a driver while I'm a teacher．他是司机,而我是老师.
(2)①some...，and others... 有些……，(剩下的一部分)有些……
②some...，the others... 有些……，(剩下的全部)其余的……
③one...，the other+n.一个……，(两者中的)另一个……
1.There are many children on the beach.Some are playing games and others are lying on the beach. 沙滩上有许多孩子，一些在玩游戏，一些躺在沙滩上。
2.There are many flowers in the garden.Some are red，some are yellow，and others are blue.花园里有许多花，一些红，一些黄，另一些蓝。
3.There are ten new books on the desk.Kate took away some of them.The others were lost.桌上有十本新书，Kate 拿走了一些，剩下的丢了。
4.I have two daughters.One is tall，and the other is short. 我有两个女儿，一个高，另一个矮。
14.The heat from the sun can't escape so the temperature is rising. 来自太阳的热量无法散去，因此温度不断上升。
(1)rise vi.(日、月、星、辰、物价、水位等)升起，上涨，上升。说明主语自身移向较高的位置。
(2)raise vt.使升高，举起。说明主语发生的动作要作用于其他事物。
(3)另外，lift 也是及物动词，意为“举起，提起，向上升”。
1.The sun rises in the east. 太阳从东方升起。
2.The price of meat has risen quickly.肉价已经迅速地涨起来了。
3.Heavy rains raised the flood stage.暴雨使洪水水位上涨。
4.He lifted the heavy box. 他举起这个重箱子。
( )1. If you need to go to the restroom in class, please _____ your hand.
A. raise B. rise C. shake D. wash
15. How can we avoid a serious water shortage
avoid (doing) sth. 避免
They built a wall to avoid soil being washed away.
他们建了一堵墙防止土壤流失。
Try to avoid going outdoors in very cold or icy weather.
在寒冷或冰雪覆盖的天气尽量不要外出。
People can keep out of the sun to avoid skin cancer.
人们可以通过躲开阳光来避免患上皮肤癌。
只接doing 的动词小结：
be used to doing sth. 习惯于干某事，enjoy doing sth. 喜欢干某事，
finish doing sth. 完成某事，practice doing sth. 练习干某事，keep doing sth. 保持干某事，
be busy doing sth. 忙于干某事，mind doing sth. 介意干某事，stop doing sth. 停止干某事，avoid doing sth. 避免干某事，give up doing sth. 放弃干某事。
have difficulty/problems doing sth. 干某事有困难，can't help doing sth. 情不自禁干某事，go on/continue doing sth. 继续干某事，have fun (in) doing sth. 愉快干某事，
spend some time doing sth. 花时间干某事；look forward to doing sth. 盼望着干某事，
succeed in doing sth. 成功干某事，make a contribution to doing sth. 为干某事做出贡献。
16.The sea seems to have the best answer. 海洋似乎有最好的答案。
seem 可用作连系动词或不及物动词，意为“似乎，好像”，常用于以下结构：
(1)“主语+seem+表语”，表语多为形容词，有时是其他的词或短语，以说明主语的特征或状态。
(2)“主语+seem+不定式”，此句型中的seem 与不定式一起构成复合谓语。
(3)“It seems+that 从句”，代词it 是形式主语，that 引导主语从句。
1.He seems(to be)quite happy. 他似乎很快乐。
2.She seemed to think the plan was useless.看上去她认为这计划无用。
3.It seems that they don't like the idea.
=They don't seem to like the idea.
=They seem not to like the idea.看起来他们不喜欢这想法。
17.Third, we should discover ways to reuse water.
(1) discover 发现 探索 v. discovery 探索 发现 n.
区别：find, discover ，invent
A. find是较非正式用词,表示找到或发现的意思。
Please find my hat for me.
B. discover指通过有意识地寻找或查询,发现某种已经存在的现象或事物。
It was Columbus who discovered America in 1492.
C. invent则表示发明以前不存在的东西。
Alexander Bell invented the telephone in 1876.
(2) reuse 重复使用 v. re- 为构词法中的前缀，意为“再一次……”
类似用法：recycle(再循环) retell(重述) return (返回) reform(重整，改革)
We can recycle plastic bottles. 我们可以回收塑胶瓶。
We should reuse water. 我们应该重复使用水。
Please retell the fairy story in English. 请用英语复述这篇童话故事。
Buy an extra ticket for the return trip. 额外再买一张返程票。
He has promised to reform. 他许诺要改过自新。