八年级下册英语第四单元知识点【推荐3篇】

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八年级下册英语第四单元知识1

副词：用来说明时间、地点、程度、方式等概念，主要修饰动词、形容词、其它副词

或整个句子。

（ 一）．副词的分类：

1．时间副词：now , then , today ,tomorrow , yesterday , before , ago , soon ,

Immediately , lately , early ,sometimes , often , always , usually , already ,

Yet , ever ,never , seldom 。时间副词是确定句子时态的重要标志，需牢记。

2．地点副词：outside , inside , upstairs, here , there , home , near , away ,

In , back , off , up , anywhere 。

3．方式副词：quickly , happily , loudly , suddenly , luckily , badly , easily ,

fast , again 。方式副词大多由“形容词 +y ”构成。

4．程度副词：very , quite , rather , too , much , so .

5． 疑问副词：when , where , why , how long , how soon , how often ,

How far . 疑问副词常用来构成特殊疑问句。

6．关系副词：when , where , why , how 等。关系副词常用来引导从句。

（一）副词的用法：

1．作状语，用来修饰动词、形容词、其它副词或整个句子。

Please listen to me carefully . The boy is too young .

Luckily , he was not badly hurt .

2. 作表语，表示方位上的变化： My father will be back in a week .

3. 作宾语补足语。 Let him in , please .

(三) 副词的位置：

1．一般副词作状语时，放在谓语动词之后，如果谓语动词之后带有宾语，则放在宾语后。

We all study hard . He is drawing a horse carefully .

2. 频度副词作状语时放在be动词、助动词、情态动词之后，行为动词之前。

He is always late for school .

I often go to see my grandparents on Sunday .

3. 某些副词为了强调上下句的衔接，放在句子之前。

Suddenly he had a good idea .

4. enough 修饰形容词或副词时，要放在形容词或副词的后面。

The boy is old enough to go to school .

He got up early enough to catch the train .

（四） 副词比较级、最高级的用法：

1．副词比较级、最高级的构成方法和形容词比较级、最高级的构成方法基本相同。

2．表示“A不如B”时，使用：A + 助动词+ not + 动词原形 + as so + 副词原形+ as+ B .

还可使用：A + 动词+ less +副词原形 + than + B

Bill didn’t do his homework as carefully as Jim .

==Bill did his homework less carefully than Jim .

3. 副词最高级前一般不加定冠词the 。

Lin Tao did best in English of all .

（五）易混词辨析：

1. hard , hardly

hard意为“努力地，辛苦地，剧烈地，猛烈地”，是程度副词。

hardly意为“几乎不”，是否定副词。

As students , we should study hard .

I can hardly catch up with you , can you walk slowly ?

2. too , also , either

too一般用于肯定句，常放在句尾；also常放在be动词或助动词之后，行为动词

之前；either用于否定句，常放在句尾。

You are a student . I am a student , too.

They are also students . I don’t like the film , either .

3. too , enough , so

too 表示 “太，很”, too …to … 表示“太。而不能、、、、、、”

enough表示“足够”， “形容词 / 副词+ enough to…”表示“足够、、、、、、能、、、、、、”。

so表示“如此”， “so … that …”表示“ 如此、、、、、、以致、、、、、、”

The man is too old to look after himself .

The boy runs fast enough to win the game .

The camera is so expensive that I can’t afford it .

4. already , yet

already用于肯定句，yet用于否定句和疑问句末尾。

I have already finished my homework .

== I have finished my homework already.

Have you finished your homework yet ?

I haven’t had lunch yet .

八年级下册英语第四单元知识2

重要词汇和句型

1.get ( 1 ) 买 get sth. for sb.== get sb. sth. 为某人买某物

Can you get some fruit for me when you go shopping?

==Can you get me some fruit when you go shopping?

( 2 ) 得到, 到达 Where did you get the book?

When did you get the letter ?He got home late last night.

(3) 使, 让 get + 宾语 + 宾补 使某人 某物 怎么样

Please get you coat clean. Get your mouth closed.

get sb. to do sth. 使某人 某物做某事

I got him to call Jim yesterday.

(4) ( 逐渐) 变得…The weather gets warmer and days get longer.

Why did the teacher get angry?

2. how about what about 后跟名词 代词 动词ing形式。

( 1) 向对方提出建议或请求

How about going out for a walk?How about something to eat

(2) 向对方征求意见或看法

How about the TV play? How about buying thehouse now ?

( 3 ) 询问天气或身体情况

How about the weather in Hainan Island ?

How about your parents? Are they living with you?

( 4 ) 谈话中承接上下文

I’m forty years old. How about you ?

I’m from Beijing . How about you?

3. receive 收到 The girl was happy to receive many gifts on her birthday.

receive aletter from == get a letter from == heard from收到某人的信

I received a letter from my parents last Sunday.

== I got a letter from my parents last Sunday.

== I heard from my parents last Sunday.

accept 接受 He couldn’t accept our suggestions but our gifts.

She was very glad to receive the invitation.

He didn’t receive a good education at university.

I received an invitation to the party, but I refused to accept it.

4. a 6--year– old child 一个六岁的孩子

6--year –old 是由 “数词 +名词 + 形容词 ” 构成的复合形容词, 作前置定语,

修饰后面的名词child .

数词+名词+形容词 构成的复合形容词，中间的名词要用单数形式：

a five-year-old girl 一个五岁的女孩

a six-foot-deep hole 一个六英尺深的洞

a two-meter-long ruler 一把两米长的尺子 a 100-meter race一场百米赛跑a ten-story-high building 一栋十层高的楼房 a two-inch-thick dictionary一本两英寸厚的词典

5. too… to… 太…… 而不能 ……

too … to… 可以与 enough to 和 so… that … 转换.

与enough to转换 时, enough 前的形容词, 副词必须是too 后面形容词,

副词的反义词, 并使用其否定句式.

She is too young to do the work .

she isn’t old enough to do the work .

与 so… that … 转换时, that 后面的从句要用否定形式.

Tom is too tired to walk any farther .

Tom is so tired that he can’t walk any farther

(2 ) 名词 , 成本, 费用, 价钱. at all costs不惜任何代价;at the cost of 以 …… 为代价.

Living costs are higher in cities than that in the country.

We must stop it at all costs .

After the earthquake, the soldiers tried to reach the area at the

cost of their lives.

7. pay, spend , cost , take 的区别

pay 花费 ( 多少钱 ) , 主语是人. Sb. pay some money for sth.

I paid 5000 yuan for the computer last week.

Spend 花费 ( 多少钱或时间 ),主语是人. Sb. spend somemoney on sth.

Sb. spend some time (in ) doing sth.

I spent 5000 yuan on the computer last week.

She spent 2 hours (in ) doing her homework .

cost 花费 ( 多少钱 ) , 主语是物. Sth. cost sb. some money.

This jacket cost him 200 dollars.

take 花费 (时间 ),It takes sb. some time to do sth.

花费某人多少时间做某事

How long does it take sb. to do sth?

花费某人多少时间做某事?

It took Liu Hong 2 hours to do her homework.

It takes me 10 minutes to walk to school from home.

It will take them 6 months to build the building.

How long does it take him to plant the trees ?

8. sleep, sleeping, sleepy , asleep, fall asleep , be asleep

sleep 动词, 睡觉, 强调动作. I am very tired. I want to sleep .

He slept for 12 hours yesterday.

sleeping, Sleep 的现在分词, 表示 “ 正在睡觉”

Don’t make so much noise. The baby is sleeping .

They woke up the sleeping girl andasked her where her parents were .

sleepy 想睡觉的, 困倦的. I am a little sleepy . I’d like to go to bed.

asleep 睡着了的.

Theteacher found Tom asleep in class andkept him behind after school .

Would you mind turning down the TV? The baby is asleep .

fall asleep 强调从没有睡着到睡着的过程, 不能接一段时间

I couldn’t fall asleep until it was very late last night.

He listened to music and fell asleep.

be asleep 表示睡着后的状态 , “ 睡着了”, 可以接一段时间 .

He was asleep for three hours.

9. choose 动词, “ 选择,挑选 ” , 过去式chose, 过去分词chosen

choose to do sth. 选择做某事

can’t Choose but 只得……

pick and choose 挑挑拣拣

There are many books to choose from .

We choose mike as our leader( 领导 ).

Will you help me choose a dictionary?

Everyone can’t choose but obey( 服从 ) .

It’s her habit (习惯 ) to pick and choose while shopping.

10. present (1) 礼物, 礼品 == gift Why not givehim a card as a present ?

what can I get him for a birthday present ?

(2 ) 目前, 现在 I’m sorry he is out at present .

You haveto forget the past and start living in the present .

11. open (1 ) 动词, 打开 , 开业, 开张, 展现

It’s not right to open other people’s letters.

Would you mind opening the window?

The door opens to the south.

This factory opened in 1998.

(2 ) 形容词, be open 开着的, 开放的

In his dream the flowers are all open .

Most shops are closed but several are still open .

On weekends the swimmingpool is open to the public .

close 动词, 关闭, 关上 , 合上

Please close the door to keep the cold out.

closed 形容词, be closed 关着的, 关闭的

when we got to the shop it was closed .

12 . give away 赠送 , 分发 give away sth to sb

Aunt Wang gave away the candies (糖果 ) to the kids .

John gave away his notebook to me .

其它短语 give up 放弃 give back 归还 give off 放出, 发出(气味)

give sth to sb == give sb. sth . 把某物给某人

13. rather than 而不是 …… 后面跟名词, 代词, 从句

The color seems green rather than blue .

If you ran rather than walked , you would have arrived earlier .

We depend on you rather than on him .

You should help them rather than they should help you .

prefer to do sth rather than do sth . 宁愿…… , 也不 ……

She preferred to stay at home rather than go with us .

He preferred to listen to music rather than play games .

Would rather do sth than do sth . 宁愿…… , 也不 ……

He would rather play than work .

I would rather take the slowest train than go there by air .

14. instead (1) 位于句首, 表示 “ 反而, 相反”

I didn’t go to the cinema last night . instead, I watched a football match on TV.

The boy didn’t sing to the music . Instead , he sang his own way .

( 2 ) 位于句尾, 表示 “ 作为代替, 而是”

Mr smith was ill , so mr green was taking his class instead .

I don’t like this one , please give me that instead .

instead of 后跟名词, 代词, 动名词, 介词短语.表示 “ 代替, 而不是”

I have come instead of my brother . He is ill .

We walked down the stairs instead of taking the elevator ( 电梯 ) .

He studies in the evening instead of during the day .

15. enter (1) 参加 == take part in join

More than one thousand sportsmen entered took part in the games .

My brother hopes to enter join the army next year .

( 2 ) 进入 ==come into go into

She entered came into the room with these words .

Did you see someone enter go into the house ?

16. encourage 动词, 鼓励, 激励 encourage sb. to do sth.鼓励某人做某事

Parents should encourage children to do things by themselves .

Our English teacher encourages us to keep a dairy in English .

17. progress 名词, “ 进步, 进展” make progress “取得进步, 取得进展”

My parents are pleased with my progress in lessons .

Tom is now making much great progress at school .

They made no progress in the heavy snow .

18. suggest 动词, 建议, 提议. 后跟名词, 代词, 动名词和从句

she suggested a way out of the difficulty .

he suggested going home .

who suggested you staying here ?

I suggested we ( should ) hold a meeting .

19. take an interest in ( doing ) sth. 对 ( 做 )某事感兴趣

否定表达是 take no interest in ( doing ) sth. 对 ( 做 )某事不感兴趣

Do you take an interest in English ?

Most children take an interest in playing computer games .

He takes no interest in playing basketball .

be become interested in ( doing ) sth对 ( 做 )某事感兴趣

I’m deeply interested in swimming .

She becameinterested in singing when she was only 7 years old .

20. Three good ways of improving English are mentioned .

提到了三种提高英语的好方法.

of improving English是介词短语作定语修饰ways . 它相当与 动词不定式.

Three good ways of improving English are mentioned .

=== Three good ways to improve English are mentioned .

Can you find a way to work out the problem ?

==Can you find a way of working out the problem ?

Fast is another way of saying quick .

== Fast is another way to say quick .

Mention (1) 动词, “ 提到, 提及, 说起 ”

as mentioned above 如上所述

He often mentioned his past to me .

Nobody mentioned anything to me about it .

Did she mention where she was going ?

You mentioned in your letter that you might be moving abroad .

As mentioned above , there are many good ways to learn English well .

( 2 ) 名词, “ 提及, 说起 ”

The newSPAper made no mention of him .

21. make friends with sb. 和某人交朋友

Would you like to make friends with us ?

I find it difficult to make friends with Ben .

八年级下册英语第四单元知识3

形容词

一、形容词

（一）形容词的含义：表示人或事物的特征、性质、状态的词叫形容词。

（二）形容词的用法及位置：

1．作定语，放在名词之前，不定代词之后。

The nice girl is my sister .

I have something important to tell you .

2. 少数形容只能作表语不能作定语：alone , afraid , ill , asleep ,awake , alive , well 。

3.作表语，放在系动词之后。 He looks happy .

4. 作宾语补足语，放在宾语之后，常与make , leave ,keep 等动词连用。

You must keep your eyes closed .

Don’t make your hands dirty .

5. 某些形容词放在定冠词the之后，表示一类人。常见的词有：good , bad ,rich , poor ,

young , old , deaf , blind, black , white , living , dead 。

The young should be polite to the old .

Please don’t laugh at the poor .

6. 某些表示情感的表语形容词后可接动词不定式（to + 动词原形）：

glad , happy ,pleased

be sorry , sad ,sure , kind + to do sth .

ready , afraid ,able

easy , difficult

(三) 形容词比较级和最高级的构成：

1．规则变化

（1）一般情况，直接在词尾加er est 。

(2) 以不发音的字母e结尾时， 加 r st 。

（3）以“辅音字母 +y ”结尾时， 把y变为 i ，再加er est 。

( 4) 部分形容词，先双写最后一个辅音字母，再加er est 。

big , hot, fat , thin , red ,

(5) 部分形容词， 在前面加 more most 。

beautiful , careful , important , delicious , difficult , dangerous

(6) 以ly结尾的形容词，在前面加more most 。

friendly(友好的) , lonely（孤独的） , lovely（可爱的）

Likely（有希望的） , daily （日常的）, lively （有生气的）

2. 不规则变化

good well --- better---best many much ---more--- most

bad ill --- worse ---worst little --- less--- least

far ---farther (较远的) further (进一步的) ---farthest (最远的) furthest （最大程度的）

old ---older(年纪较大的) elder（年纪最大的）---oldest（较年长的） eldest (最年长的)

(四) 形容词原级的用法：

1．说明人或事物自身的性质、特征或状态时用形容词原形。

The flowers in the garden are beautiful .

2. 有表示程度的副词very , so , too,enough , quite 等修饰时，用形容词原形。

The boy is too young .

3.表示A与B在某方面程度相同或不同时，用形容词原形。

肯定句：A + 动词 + as + 形容词原形 + as + B 。

English is as interesting as Chinese .

Xiao Ming is as tall as Jim .

否定句：A + 动词 + not as so+ 形容词原形 + as + B 。

This book is not as so new as that one .

I am not so careful as Lucy .

否定句的结构相当于 A + 动词 + less + 形容词原形 + than + B 。

He thinks Chinese is less interesting than English .

4. 表示“A 是B 的几倍”： A +动词+ 倍数+ as + 形容词原形 + as + B 。

Our school is three times as big as theirs .

This table is twice as long as that one .

5．“A + 动词 +Half + as + 形容词原形 +as + B”表示“A是B的一半”

Her room is half as big as yours .

(五)、形容词比较级的用法：

1．表示两者进行比较时，用形容词比较级：A + 动词+ 形容词比较级 + than + B

Lily’s room is bigger than mine .

This mooncake is nice than that one .

2． 有表示程度的副词a little , a bit , a few , a lot , much , even , still ,

Far , rather , any 等修饰时，用形容词比较级。

I feel even worse now . It is much colder today than before .

3. 表示两者之间“哪一个更、、、”：which who is +形容词比较级, A or B ?

Who is taller , L i Ming or Wang Tao ?

Which sweater is more beautiful , the yellow one or the pink one ?

4. 表示“几倍于、、、、、、”时， 用“A + 动词 + 倍数+比较级 + than + B ”

I am three years older than you .

5．表示“两者之间较、、、、、、的一个”，常用 “the +比较级”结构 。

Mary is the taller of the twins .

6. 表示“越来越、、、、、、”时，用比较级重叠结构，即“比较级 +and + 比较级 ”，多音节

词和部分双音节词用“more and more +形容词原形 ”

It’s getting warmer and warmer in spring .

Our hometown is becoming more and more beautiful .

7. 表示“越、、、、、、就越、、、、、、”时，用“the +比较级 , the +比较级 ”

The harder he works , the richer he is .

The more we get together , the happier we’ll be .

(六)、形容词最高级的用法：

1．三者或三者以上的人或物进行比较时，用形容词最高级。形容词最高级前必须加定冠词

the , 句末常跟一个in of 短语来表示范围。

He is the strongest of the three boys .

Shanghai is the biggest city in china .

2. 表示“三者或三者以上的人或物，哪一个最、、、、、、？”用句型：

Which who is + the + 最高级 , A , B , or C ?

Which city is the most beautiful , Beijing , Shanghai or Fuzhou ?

3. 表示“最、、、、、、的、、、、、、之一” 时，用句型：

主语 + is + one of the +形容词最高级 +名词复数 。

Zhou Jielun is one of the most popular singers .

4. 形容词最高级前面可加序数词，表示“第几大 / 长 / 高 等”

Changjiang River is the first longest river in China .

5. 形容词最高级前面可以有物主代词、指示代词、名词所有格等修饰，此时不用the 。

This is our last lesson . Yesterday was his busiest day .

6. 形容词比较级结构可以表示最高级含义。

Li Lei is the tallest student in his class .

== Li Lei is taller than any other student in his class .

== Li Lei is taller than the other students in his class .

== Li Lei is taller than anyone else in his class .

==No one is as tall as Li Lei in his class .

==No one is taller than Li Lei in his class .

== Li Lei is taller than any of the other students in his class .

== Li Lei is taller than the rest of students in his class .

（七）、--ing 形容词与--ed 形容词：

--ing 形容词表示“令人、、、、、、的”， 表示主动意义，多指事物对人的影响，一般修饰或说明事物。如：surprising（令人惊讶的） , exciting （令人兴奋的）, interesting（有趣的） 等。--ed 形容词表示“感到、、、、、、的”，表示被动意义，多指人对事物的感受，主语一般是人：sb. + be +--ed 形容词 + 介词短语 。 如：surprised(感到惊讶的) , excited（感到兴奋的） ,

Interested（感到有趣的） 等。

We are all excited about the exciting news .

（八）在同一范围内比较时，必须把主体排除在被比较的范围之外。

China is larger than any other country in Asia .( 在同一范围内)

China is larger than any country in Africa . (在不同范围内)