八年级上册牛津英语U1-U8知识点归纳

八年级上册牛津英语U1-U8知识点归纳
八年级上册牛津英语U1-U8知识点归纳

语法

1. 第一组的球员比第二组球员踢得好得多。

The players in the first group played much better than those in the second group.

2. 他的狗比我的大两岁

His dog is 2 years older than mine.

3. 我认为跑步没有(不如)游泳有趣(2)

I don?t think running is as interesting as swimming.

I think running is less interesting than swimming

4. 他的重量是我的两倍

His weight is twice as much as mine.

5. 他是双胞胎中更健康的那个。

He is the healthier of the twins

6. 你吃得越多就越胖。

The more (food) you eat, the fatter you will be.

7. 老虎的数量越来越少。

The number of the tigers is smaller and smaller

8. 中国学生比美国学生放假少

Chinese students have fewer days off than American students.

9. 他是班里最聪明的学生(3)

He is the cleverest student in the class.

He is cleverer than any other student in..

He is cleverer than the other students in…

10. 北京比日本任何一个城市都大。(2)

Beijing is bigger than any city in Japan.

Beijing is bigger than the cities in Japan.

11. 我的校服和他的截然不同。

My school uniform is quite different from his.

11. 当我路过他窗口时,风刮得厉害。

When I passed his window, the wind was blowing hard / strongly

12. 或许他会死。(4)

Maybe he will die

Perhaps he will die

He may die

He will possibly die

13.要得第一的话,你自己最好多练习打球。

(in order ) to get the first prize

To come first, you yourself had better practise playing balls more.

14. 我使她感觉无聊 I make her feel bored

我让她打扫卫生 I ask = tell her to clean it

我让她一直打扫卫生 I keep her cleaning it

我让灯关着 I leave the lights off

谢谢你同意让我参加晚会

Thank you for agreeing to let me take part in the party.

15. 当我到家时,我看见妈妈烧饭。

When I arrived home , I saw my mother cooking

16. 没做成 fail to do

17. 拒绝做 refuse to do

U1

thirsty honest secret joy=happiness teenager(s) magazine good-looking humorous impolite impolitely tidier trust lie lying joke true truly truth generous willing voice singer almost round sense bored boring fitted knock straight sweet smile smiling personality chose worse worst height weight weighed second test competition swimmer planned social society ponytail slimmer shier square handsome hard-working work hard hard work impatient unhappy

excellent fatter hungrier

have something to do

what about doing

some more food

can I have two more cakes

another two cakes

there is no fridge.

there are no fridges.

share sth with sb

invite sb to take part in / join in the party. what makes your friend so special?

what makes good friends?

I make you keep a secret for me

I keep a secret to myself

I keep it secret

tell lies

tell us jokes

I don?t think riding is as interesting as driving. agree with sb to do

one of the longest rivers

be generous to sb

be willing to do

be ready to help

help (sb) with 名( study)

give the seat to someone in need on the bus have a good voice

he wants to be a scientist when he grows up grow into a big tree.

make him look smart

has a good sense of direction / humor

feel bored with him.

20 people can fit in the room

walk past = pass

knock sth over 翻/ off 离/ onto到..上

knock on / at the door

say a bad word about others

a true friend

When something worries me , I choose to do…

I worry about you

=I am worried about you

choose one from 12 people

for further study

The drawing competition he height of sth is what is the height of

the weight of sth is what is the weight of

the number of sth is what is the number of

A number of s th are…

the cost of sth is high / low what is the cost of

the price of sth is what is the price of

be famous as / for

be popular with / among

listen to people?s problems and help them with their problems travel around the world

future plans

works of art

learn more / much /a lot/ little/ less about

on the left

this is… (speaking)

what is sth like? –形容词回答

What is the weather like= how is the weather

what does sb look like?- 外貌

a girl with a ponytail

dark brown eyes

the hard work makes the hard-working boy work hard. both A and B

first do = do ..for the first time

bright smiling eyes

wear / have a smile on the face

be patient with sb

work with sb

make / be an excellent teacher

an advertisement British Britain America American biscuit(s) cookie(s) lorry truck rubber eraser football soccer holiday vacation autumn fall shop store garden yard film movie mixed French France foreign foreigner(s) language(s) during discuss discussion(s)

in class offered end baseball win won winner winning least further furthest spend spent uniform chess at most daily weekly monthly yearly at first look through real really

Keep on doing keep doing keep sb doing Keep 形 keep sth 形/介 finish doing = complete doing lunchtime physics badminton an ideal school chatted heroes

1.Why don?t you do.. = why not do..表示建议 Why not?表示同意

2. Work harder

3. What is sth like? – It is like doing sth 注意回答

4. fewer advertisements

5. chat with sb

6. buy sth for sb = buy sb sth

7. a toy lorry

8. would like to do (want to do)

9. have plans for the weekend 10. shall we….? 11. life in a British school = school life in Britain 12. in Year Eight = in Grade Eight = in the eighth grade 13. A mixed school 14, have lessons together 15. among all my subjects 16. I like sth best = My favourite is sth 17. Doing sth is fun 18. borrow sth from sp 19. lend sth to sb = lend sb sth 20. near the end of each class 21. discuss sth with sb 22. Time seems to go fast(er)

It seems that time goes fast(er) 23. the Buddy Club

24. on Friday afternoon

25. our school ends earlier than usual 26. do sports 27. twice a week

28. practise playing balls hard 29. win two games / sth

30. last month / week 前无介词 31. listen to heroes? problems 32. what else / who else

33. among the three of us = among us three 34. have less free time

35. come first = get the first prize in the race 36. he can draw the best of us

37. how long / how far / how often / how many times / how much time 38. wear uniforms / be in uniform

39. do morning exercises 40. have(take) fewer days / weeks off 41. spend 时间 doing spend 钱 on sth 42. have a monthly test 43. learning foreign languages is really fun 44. too early or too late 45. My school starts at…. and finishes at… 46. go on a (school) trip (to sp) 47. don?t need to do 48. need do 49. have an hour of homework 50. a dining hall 51. at lunchtime 52. wear ties / a tie 53. choose subjects to study 54. after-school activities 55. have fun doing = have a good time doing = enjoy doing 56. what fun we have doing sth! What a good time we have doing sth!

ourselves yourselves themselves Australia Australian coffee top president(大写?) wide steel ton(s) fine(副) shine(动/名) shone shining shiny sunshine clear(动/形) clean(动/形) sky journey trip tour finally arrive at 小/in 大 reach sp get to sp can?t wait to do/ can?t wait for sb can?t stop doing get off/on it

places of interest be interested in doing show interest in doing do..with interest(s) believe one?s eyes main mainly sights culture(s) cultural Internet home pages by oneself pull push rock luck lucky luckily climber final(形/名) support(名/动) supporter take place=happen cheer for sb cheer sb up ticket be cheerful cheer(名)

half-time the cost of sth is rest(动/名) for free helpless helpful useless useful endless hope(名/动) mean meaning meaningful taste tasty colourful keep sth for a week square exercise(锻炼不可数)

need to do don?t need to do

need sb to do don?t need sb to do

need do needn?t do

keep fit = keep healthy

it is as high as the real one

enjoy ourselves

an invitation letter

take a boat trip

the Harbour Bridge

the Opera House

by the river

(on) the top of the Eiffel Tower

the White House

a building with a garden

the President of the USA

Flat One

search for information

the Golden Gate Bridge

It is 1.1 feet long / wide/ high.

it is made of 看得出

It is made from 看不出

It is made in 地点

- it is good, isn?t it?

- yes, it is good. I like it very much.

- no, it isn?t good. I don?t like it.

I did fine

a school trip to sp

a fine warm day

the sun was shining in a clear blue sky

it is quite far away (from sp)

it took sb half an hour to do.. 某人要半小时做

there is a lot of traffic.

on the way ( to sp)

the whole world

in front of 有the 无the

the model Eiffel Tower

models of places of interest

from all over the world really tall it looks as great as the one back home the real one an amazing day I am amazed in / within just one day the song and dance shows different cultures get sth on / from the Internet on the home pages take photos of sb with sb for yourselves it looks like the real one take part in the visit(s) in some ways learn French in France help oneself to fruit teach oneself sth / to do learn sth / to do by oneself my own food on my own = by myself = alone say sth to oneself the competition itself is just a game pull oneself up the rocks hurt oneself get to the (basketball) final = be in the (basketball) final sth take place sth happen to sb don?t forget to bring sth here take sb to sp forget doing with teachers? support,… go back to school = return to school the cost of the trip is 10 yuan per student by underground 20 minutes? walk / ride/ drive --- how far

at noon

groups of 20 (or more

students)

the day before yesterday

row a boat

plan a day out

make sth1 sth2

instructions had better = …d better brushes glue tool rope(s) scissors tape(s) DIY exactly correctly certainly actively incorrect uncertain inactive stand for repair = fix decorate

decoration instead (of..) rose crazy crazier terrible terribly once put in put up sb makes a mistake sth goes wrong(副) My car broke down. It had a power cut pipe fill… with… not only… but also ceiling shelves advise advic e(不 ) course already attended cut

(过) cut out sentence grape strawberries spoon salad cream sauce mixes added tip(s) an example for example leave – left – left ham finished impossible untidy tidy up spell - spelt balloon stick- stuck cover complete(动/形) paint(动/名不) furniture(不可数)

read the instructions first I says“Do it yourself” what is DIY exactly? do DIY (jobs) instead of paying someone to decorate the room make paper roses a pair of scissors something new

be crazy about sth / doing decorate the house

repairing things = fix things = mend things be fixed to the wall be terribly sorry put in a light

put up a picture on the wall

put out / put away / put on hit a pipe

he fills the room with water the room is filled with water the room is full of water

he thought his room was boring paint / colour sth blue

he is famous not only in China but also in the world. he is not only helpful but also careful.

he plays not only basketball but also football.

he not only decorates his house but also repair it.

Not only students but also the teacher takes a course in DIY a shelf above my bed one end of the shelf

advise sb not to put in a light on the other end of the shelf attend a meeting / lessons fail to do

cut out pieces of card cut them into pieces

on the other side of the card sth is broken

my car broke down

had better not be late for school / work again without doing

add cream to fruit if you like

make sure it is fresh 确保 be sure 确信 相信 fruit of different colours mixing ….will make fruit look as good as it tastes

fruit in season looks as good as it tastes

U5

wild wildly dishes pity ( pities) die died dying dead death in fact dolphin giant pandas squirrel zebra was born at birth in the beginning sadly facing seriously live mainly on however otherwise as a result in danger take action(s) right away natural nature reserve laws none neither

closed-open bat bee get/be lost lose save safe safety safely stripe while qualities hunter caught wolves thicker make a living kill humans yours sincerely sorry sell out sell well a shame act to do illness because of doing accept receive report tail insect move slowly daytime

I don?t think so.

they may become dishes on the table have/ take pity on a report on an animal

the king of the animal world the story of Xi Wang

when she was ten days old = at the age of ten days call sth1 sth2

A means

B = the meaning of A is B

sb weighs 10 kilograms = the weight of sb is 10 kilograms = sb is 10 kilograms in weight she was not a baby any more = she was no more a baby look after sb well = take good care of sb sadly, sb face serious problems in the wild.

make a good example

for example

it is difficult for pandas to have babies

live mainly on a special kind of bamboo

have no place to live in = have nowhere to live

be in / out of danger (of doing)

take action to do

make laws to do

in order (not ) to do = so as to do

in order that = so that 句子

protect sb from doing

prevent / stop / keep sb from building farms

if there is no nature reserve the natural world

Soon there may be none left

no giant pandas left

there may be nothing / nobody.

where there is Xi Wang, there is hope.

none of them is / are happy

neither of them is happy

stand with eyes closed

agree to do

prepare to do

hope to do decide to do fail to do plan to do refuse to do

teach sb to do

I advise him to do

what to do how to do it

work out easy maths problems

bats can?t see

they fly in the right way with the help of their mouths

and ears

they came back the same way as they went

catch / kill sb for fur / for fun

be able to do

work as a team without stopping

be dangerous to humans

I am sorry to hear that.

animals? fur

you bought fur coats

what a shame

thank you for accepting my invitation

I have feelings of happiness and sadness

thank you for your kindness

receive

sleep through the winter

in the daytime at night

seem to stand with eyes closed U6

birdwatching birdwatcher market hen crane red-crowned cranes sparrow feathers

swan an eagle broad wings type(s) rare wetland provide prevent protect cover(不 ) wildlife perfect all year round/ around stay easily per cent space lead led to moreover fishermen fish government record change tourist visitor traveller count describe description understood importance write down cover A with B A is covered with B a pair of binoculars clearly speaker tour application form address chairperson introduce introduction

watch the birds go birdwatching sure = certainly at the market the science teacher the scientist encourages us to join the Birdwatching Society the red-crowned crane with grey feathers and a long thin neck how many types of cranes are there ? - none lives in north-eastern China in the north-east of China Zhanglong Nature Reserve is one of the world?s most important wetlands Heilongjiang Province provides rice for us = provide sb with sth it is a perfect place for a short stay / while most birds = most of the birds 40 percent of the birds are = 40 per cent birds are active in the daytime watch sth easily having / making more space for farms will lead to fewer and fewer living areas less and less space moreover, …. have enough food comfortable enough quickly enough

Let?s prevent accidents from happening record the changes in their numbers Study the birds count the birds do a bird count

count from 1 to 100

understand the importance of protecting nature feed the birds

Studying Zhalong helps us learn about protecting wildlife.

Take a notebook with you in order to write down what you see. fly south for winter

be home to sth 这里home 不可数

he reserve covers an area of 100 square kilometers sth is 100 square kilometres in area. before doing after doing

when / while / as doing 不 加句子,就是doing

a pair of binoculars what else should we take when we go birdwatching you may get thirsty make different bird sounds , including birds are part of our lives make an application fill in an application form call s

b on 号码 email sb at 邮箱 from … to / till….. between … and …. join the Birdwatching Society let me introduce him to you make an introduction to sth

U7

betted foggy rainy snowy cloudy cloudier butterflies shower(s) memories stream screamshade piles of .. Build a snowman upon=on harvest crops temperature(s) dropped fell threw rise rose clouds kick a high fever coughed a lot awful snowstorms wind around=about sunshine rest (名、动) degrees a bit 比较 a bit of 名词 blew loud / loudly louder/ more loudly ring rang fog sleepy fall asleep shine名 shiny shining sudden cause snowball fights deep frozen land(不) exciting excited threw snowmen ice everywhere

fly flew hide hid lazier

bring sth to sb = bring sb sth

sb look cool in 衣服

= 衣服 looks cool on sb

I bet you will…

it is the best time to play outside

seasons of the year

A is full of snow

grow up

grow into….

what a perfect time (it is) to fly a kite! play among flowers

hide (sb) from April showers

those sweet memories

under/ in the shade of sth

leaves turn brown

fall into piles upon the ground

harvest crops

as the days are shorter

A rhymes with B

on a hot summer afternoon

be busy doing

be busy with 名词

be busy at work

what is the weather like

how is the weather

drop / rise to 10 degrees

by 10 degrees

below 10 degrees

above 10 degrees

stay above / below 1 degree

build sth for sb

build sb sth

woke up / got up

there are clouds

it is cloudy 区别

It is rainy I hate rainy days it is raining区别

catch a bad cold

have a high fever what bad weather it is!

snowstorms from the north will arrive

in the late afternoon

minus 10 degrees = 10 degrees below zero

it will mainly be cloudy and dry.

it will turn cloudier

the temperature will be around 1 degree

during the day = in the daytime

it is hot, with temperatures in the forties

for the rest of the week

the rest of the week is…..

the rest of the students are

the temperature is high / low

the temperature can be so different in different places during this time of year

on the phone

this is sb speaking

how are you doing = how are you

a strong snowstorm / wind

heavy rain / fog/ snow

thick fog 以上都是名词

the wind blows strongly / hard

it rains heavily / hard

it snows heavily / hard

I can?t hear you cleary

speak a bit louder / more loudly

I will ring you later.

people in the street have to cover their faces with scarves

the sudden heavy rain

the best season of the year

have snowball fights

fight fought

fight with sb / against sb for sth

healthier noisier noisily

throw snowballs at each other, screaming and laughing. make snowmen

use carrots for their noses

the Ice Festival

….everywhere

cough a lot / badly

U8

disasters mop up eat up die out earthquakes thousands of accidents coach crash into floods wash away village countryside lightning thunder storms catch fire slight shake shaking shook bombs fear fearful fearfully directions in all directions while bricks come down fall down silent silence if(两意思) hurt过not…at all nervous hit hit hitting hearts beat trapped mind calm down since still be alive dark find one?s way out shout (名、动) at last daylight safe safer asleep after broke down as..as possible towels rules railway(s) burn(动、名) daughter granddaughter son grandson behind board(s) weekday(s) headache toothache housework pancakes

is all wet

hear the rain

hear the wind blowing hard

mop up

the geography teacher

an article on natural disasters

lose the final

a car accident kill thousands of people

crash into a tree

start a big fire

make a fire

catch a fire

be on fire

get into the building on fire

the building is on fire

fall off the tree

from the tree

over / down

onto the ground

what happened to him?

hear about / of sth

from sb

sth

a heavy storm with thunder and lightning

lightning hit a classroom building

sb was hurt

sb hurt 部位

sb survive the earthquake

feel a slight shake/ shaking

heard a loud noise like thunder

scream in fear ( of losing his life)

run in all directions with excitement

excitedly

tried their best to run out (of the building) pieces of glass and bricks were falling down It was dark and silent around me

I could not see anything at all I will not go out if it rains tomorrow

my heart was beating fast

I am trapped

a moment of fear goes through my mind.

Since everybody is her e, let?s start the meeting. shout for help

hear shouts from excited people

pull myself slowly through the dark

there is enough space for me to move

hours later,….

Hear the noise above me

move away sth

from side to side

up and down

An earthquake happened in Taiwan

An earthquake hit Taiwan

stand on the side of the road

wait for sb to do

because of the cold weather

get out as soon as possible

stay low to the ground

walk through the flood

hide under a strong desk

follow traffic rules

break traffic rules

look left and right when you cross the road

on railways

the railway station

yesterday?s talk

keep ourselves safe from fires, floods and earthquakes

stay away from

keep away from

keep your hand in cold water

cover the burn with a clean towel

lose my umbrella

the next morning

sb couldn?t get home that night because of the heavy snow

I am not sure/ don?t know if it will rain

新人教版八年级上册英语知识点总结大全

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初二英语知识点总结

初二英语知识点总结: (一) 一般将来时 一般将来时表示将来某个时间要发生的动作或者存在的状态。通常与表示将来的时间状语连用,如tomorrow, the day after tomorrow, next year, next month, next week, in 100 years等。 be going to do (动词原形)结构:表示打算、准备做的事情或者肯定要发生的事情。如:It is going to rain. will do 结构表示将来的用法: 1. 表示预见 Do you think it will rain? You will feel better after a good rest. 2. 表示意图 I will borrow a book from our school library tomorrow. What will she do tomorrow? 基本构成如下: 一般疑问句构成: (1)will+主语+do…? Will Sarah come to visit me next Sunday? (2)there be 结构的一般疑问句:Will there + be …? Will there be fewer trees? Yes, there will. / No, there won’t 否定句构成:will + not (won’t)+do Sarah won’t come to visit me next Sunday. 特殊疑问句构成: 特殊疑问词+will+主语+…?What will Sarah do next Sunday? 根据例句,用will改写下列各句 例:I don’t feel well today. (be better tomorrow) I’ll be better tomorrow. 1. Gina has six classes today. (have a lot of homework tonight) _____________________________ 2. I’m tired now. (sleep later) _____________________________ 3. My parents need a new car. (buy one soon) _____________________________ 4. We can’t leave right now. (leave a little later) _____________________________ 5. The weather is awful today. (be better tomorrow) _____________________________ 答案:1. She’ll have a lot of homework tonight. 2. I’ll sleep later. 3. They’ll buy one soon. 4. We’ll leave a little later. 5. Maybe it’ll be better tomorrow. (二)should的用法:

人教版八年级上册知识点总结汇总

第一章机械运动 一、长度和时间的测量 1.长度的国际单位:米(m) 1km =103m 1m=10dm=100cm=103mm=106μm=109nm 2.长度测量的工具是:刻度尺、游标卡尺、螺旋测微器等。 3.刻度尺的使用 ①观察:零刻度线、量程、分度值 ②放置:零刻度线或整刻度线对准所测物体的一端;有刻度的一边要紧靠被测物体且与被测边保持平行 ③读数:视线正对刻度线;估读到分度值的下一位 ④记录:数值+单位 4.时间的单位:秒(s);常用单位换算:1h=60min=3600s. 5.时间的测量工具:钟、表、停表(秒表) 6. 误差:测量值和真实值之间的差别. ①减小方法:多次测量求平均值、选用精密测量工具、改进测量方法 ②误差与错误的区别 误差:不可避免,不能消除误差;错误:不该发生的,能够避免; 二、运动的描述 1.机械运动:物体位置随时间的变化 2.参照物:在研究物体的运动时,选作标准的物体 ①判断运动状态:被研究的物体相对于参照物的位置变化→运动(不变→静止) ②参照物的选择:任何物体(运动的、静止的)都可以;通常选地面为参照物;参照物不同,同一个物体运动状态可能不同;运动和静止的相对性 三、运动的快慢 1.比较物体运动快慢的方法 ①在相同时间内,比较物体经过的路程——观众方法 ②物体经过相同的路程,比较所花的时间——裁判方法 2速度:路程与时间之比.(采用方法①定义) ①公式:v= 路程(s)——米(m)——千米(km)

时间(t)——秒(s)——小时(h) 速度(v)——米/秒(m/s)——千米/小时(km/h) ②单位换算:1m/s=3.6km/h 3.匀速直线运动:物体沿着直线且速度不变的运动 ①任意相等时间内通过的路程总相等 ②运动方向和速度都一直保持不变 ③图像 四、测量平均速度 (1)原理:v= t s (2)测量工具:刻度尺(测路程)、停表(测时间) (3)斜面保持很小的坡度的目的:便于测量时间; (4)金属片的作用:使小车在确定位置停下,便于计时; (5)步骤:按如图组装;测量路程;释放小车测量时间;计算速度;(6)若过了起点才开始计时,时间偏短,速度偏大 (7)结论:小车从斜面顶端滑致底端的过程中,做变(加)速直线运动; 且v 下半>v 全 >v 上半 第2章声现象 一、声音的产生与传播 1.声的产生:声是由物体的振动产生的。 2.声的传播 ①声音的传播需要介质,声音不能在真空中传播 ②声音可以在固体、液体、气体中传播,一般v 固>v 液 >v 气 ,

初二英语知识点总结知识讲解

初二英语知识点总结

初二英语知识点总结: (一) 一般将来时 一般将来时表示将来某个时间要发生的动作或者存在的状态。通常与表示将来的时间状语连用,如tomorrow, the day after tomorrow, next year, next month, next week, in 100 years等。 be going to do (动词原形)结构:表示打算、准备做的事情或者肯定要发生的事情。如:It is going to rain. will do 结构表示将来的用法: 1. 表示预见 Do you think it will rain? You will feel better after a good rest. 2. 表示意图 I will borrow a book from our school library tomorrow. What will she do tomorrow? 基本构成如下: 一般疑问句构成: (1)will+主语+do…? Will Sarah come to visit me next Sunday? (2)there be 结构的一般疑问句:Will there + be …? Will there be fewer trees? Yes, there will. / No, there won’t 否定句构成:will + not (won’t)+do Sarah won’t come to visit me next Sunday. 特殊疑问句构成: 特殊疑问词+will+主语+…?What will Sarah do next Sunday? 根据例句,用will改写下列各句

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八年级上册知识点归纳总结

第十二章平面直角坐标系 12.1平面上的点的坐标 定义:平面上互相垂直且有公共原点的两条数轴构成平面直角坐标系,简称为直角坐标系 2、各个象限内点的特征: 第一象限:(+,+) 点P (),则x >0>0; 第二象限:(-,+) 点P (),则x <0>0; 第三象限:(-,-) 点P (),则x <0<0; 第四象限:(+,-) 点P (),则x >0<0; 3、坐标轴上点的坐标特征: x 轴上的点,纵坐标为零;y 轴上的点,横坐标为零;原点的坐标为(0 , 0)。两坐标轴的点不属于任何象限。 4、点的对称特征:已知点P(), 关于x 轴的对称点坐标是(), 横坐标相同,纵坐标反号 关于y 轴的对称点坐标是() 纵坐标相同,横坐标反号 关于原点的对称点坐标是() 横,纵坐标都反号 5、平行于坐标轴的直线上的点的坐标特征: 平行于x 轴的直线上的任意两点:纵坐标相等; 平行于y 轴的直线上的任意两点:横坐标相等。 6、各象限角平分线上的点的坐标特征: 第一、三象限角平分线上的点横、纵坐标相等。 第二、四象限角平分线上的点横、纵坐标互为相反数。 7、点P ()的几何意义: 点P ()到x 轴的距离为 , 点P ()到y 轴的距离为 。 点P ()到坐标原点的距离为 22y x 8、两点之间的距离:

X 轴上两点为A )0,(1x 、B )0,(2x ||12x x -= Y 轴上两点为C ),0(1y 、D ),0(2y ||12y y -= 已知A ),(11y x 、B ),(22y x 212212)()(y y x x -+- 9、中点坐标公式:已知A ),(11y x 、B ),(22y x M 为的中点 则:(212x x + , 2 12y y +) 12.2点的平移特征: 在平面直角坐标系中, 将点()向右平移a 个单位长度,可以得到对应点( ,y ); 将点()向左平移a 个单位长度,可以得到对应点( ,y ); 将点()向上平移b 个单位长度,可以得到对应点(x ,y +b ); 将点()向下平移b 个单位长度,可以得到对应点(x ,y -b )。 注意:对一个图形进行平移,这个图形上所有点的坐标都要发生相应的变化;反过来, 从图形上点的坐标的加减变化,我们也可以看出对这个图形进行了怎样的平移。 第13章 一次函数 13.1一次函数 1、变量:在一个变化过程中可以取不同数值的量。 常量:在一个变化过程中只能取同一数值的量。 2、函数:一般的,在一个变化过程中,如果有两个变量x 和y ,并且对于x 的每一个确定的值,y 都有唯一确定的值与其对应,那么我们就把x 称为自变量,把y 称为因变量,y 是x 的函数。 *判断A 是否为B 的函数,只要看B 取值确定的时候,A 是否有唯一确定的值与之对应 3、定义域:一般的,一个函数的自变量允许取值的范围,叫做这个函数的定义域。 4、确定函数定义域的方法: (1)关系式为整式时,函数定义域为全体实数; (2)关系式含有分式时,分式的分母不等于零; (3)关系式含有二次根式时,被开放方数大于等于零; (4)关系式中含有指数为零的式子时,底数不等于零;

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