八年级 下 1--5单元 易错题

Units 1---5 易错题

一．单项选择 1.( ) You don’t look _______ . Y our face looks ________ red.

A. good; a little

B. well; a bit

C. bad ; a bit of

D. better ; a bit

2.( ) --- Could I _______ your bike? ----- Sorry, I ________ it ______ Jim yesterday.

A.lend; borrow ; from

B. borrow ; lent ; from

C. lend ; lend ; from

D. borrow ; lent; to

3.( ) She often provides food and clothes _________ the homeless children.

A. of

B. with

C. about

D. for

4.( )We decided to make some signs to _________ around our school.

A．catch up with B. put off C. put up D. give up

5.( ) --- The volunteers are___ money for a sick girl in the park. --- Let’s go to help them.

A.turning

B. raising

C. getting

D. giving

6.( ) ---- You should put a bandage ____ it when you cut your knee.----- Ok, thanks.

A.at

B. on

C. in

D. with

7.( ) We will wait for you until you __________ back tomorrow.

A. come

B. will come

C. is coming

D. came

8.( ) She __________ in the kitchen when I ___________ to see her yesterday.

A. cooked; went

B. was cooking; was going

C. cooked ; was going

D. was cooking ; went

9.( ) I can’t go with you because I have _________ homework to do.

A. much too

B. many too

C. too much

D. too many

10.( ) Mr. Black talked about his son with the teacher ________ the phone.

A. by

B. on

C. in

D. with

11.( ) Her mother doesn’t allow her _________ with her friends on weekends.

A. to hang out

B. hang out

C. hanging out

D. hanged out

12. ( ) Jim was standing there with his back _________ a big tree.

A. against

B. beside

C. below

D. across

13.( ) You have to leave now __________ you can catch the early bus.

A. as soon as

B. so that

C. until

D. while

14.( ) Once the actor Edwards told his fans, “Be yourself and don’t let anybody ___ you around.” A. pull B. turn C. take D. push

15.( )Tom seems to have a cold because the weather changes ________.

A. slowly

B. suddenly

C. clearly

D. carefully

16.( ) Dr. Smith ______ working though he felt terrible.

A. stopped

B. remembered

C. enjoyed

D. continued

二．用所给词的适当形式填空

1.His ____________ (kind) saved the old man’s life in time.

2.At last he make a good ____________ (decide) on where to travel.

3.Teenagers should study hard because you are the ________ (own) of the future world.

4.“Don’t play computer games all the time.” The mother said __________ (angry).

5.They don’t have enough time ____________ (do) what they like.

6.They don’t understand why some parents make their kids __ (help) with chores at home.

7.Also, when they get older, they ____________ (have) to do housework so there is no need

for them ___________ (do) it now.

8.___________(do) chores helps to develop children’s ______________ (depend) and teach

them how to look after _____________ (they).

9.He is ___________ (true) talented in music. Can you tell me the _______ (true)?

10.___________ (sudden), she turned around and looked at me .

11.The road is _________ (ice) . You should be careful.

12.My brother collects different kinds of ___________ (match).

https://www.wendangku.net/doc/0f6642548.html,cation is important to a country’s ______________ (develop).

14.I found my mother _____________ (look) through my things yesterday.

15.We tried _______________ (not make) any noises because the baby was sleeping.

16.Would you mind ___________ (copy) the paper for me?

17.I don’t remember ____________ (see) him anywhere.

18.He kept _____________ (look) at his watch in his office all the afternoon.

19.Could you please __________ (wake) me up tomorrow?

20.He got up and __________ (read) an evening newspaper until the match began.

21.The ____ (early) kids learn to be independent, the ________ (good) it is for their future.

22.This math exercise isn’t difficult. I can finish it ______(easy).

23.I used to _______________ (get) up early.

24.Jim is used to ____________ (walk) to school.

25.Parents should teach their kids how to be ______________ (independence).

26.Why not ___________ (give) him a glass of water, Jim?

27.Too much pressure is not good for a child’s _______________ (develop).

28.Mr. Chen is a __________ (type) good teacher. He loves his students and teaches well.

29.Many parents are always ______________ (compare) their kids with other children.

30.When he got home, he found ___________ (break) windows and rubbish everywhere.

31.My father was so tired that he fell ____________ (sleep) quickly.

32.She has a ____________ (stomach). She doesn’t want to eat anything.

三．用括号中所给动词的适当形式填空(12分，每空1分)

Wang Lei is from Number 16 School. She is used to _1__________ (get) up early. She thinks it’s very important for children _2__________ (learn) to be independent. So she often does some chores such as _3___________ (do) the dishes and folding the clothes. At the same time, she takes after her father, and she volunteers her time _4__________ (help) other people. While she _5____________(walk) on the street at 9 o’clock last Sunday, she saw an old man _6___________ (lie) on the side of the road. She stopped without _7________ (think) twice and _8________ (take) the man to the hospital. _9__________ (thank) to Kate, the doctor saved the man in time.

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．C D． 13．（金华）小明在一直道上骑自行车，经过起步、加速、匀速、减速之后停车．设小明骑车的时间为t（秒），骑．C D． ﹣0.5x﹣1中，一次函数有（） 14．下列函数：①y=﹣8x、②、③y=8、④y=﹣8x2+6、⑤y= ） 16．已知点（﹣4，y1），（2，y2）都在直线y=﹣x+2上，则y1，y2大小关系是（ 18．（清远）计算：（π﹣3）0+2﹣1=_________． 19．等腰三角形的周长是16，写出底边长y与一腰长x的函数关系式____，自变量x的取值范围是________．20．（贵州模拟）在函数y=中，自变量的取值范围是_________． 21．已知函数y=（k﹣1）x+k2﹣1，当k_________时，它是一次函数，当k=_______时，它是正比例函数．22．（包头）若一次函数y=ax+1﹣a中，y随x的增大而增大，且它的图象与y轴交于正半轴，则|a﹣1|+= _________． 23．（襄阳）若一次函数y=2（1﹣k）x+k﹣1的图象不过第一象限，则k的取值范围是_________． 24．将直线y=2x沿x轴的正方向平移1个长度单位，得到直线_________． 25．直角坐标系中，直线y=2x+3关于原点对称的解析式为_________． 三．解答题（共5小题） 26．通分：，．

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第一章 三角形的证明
1.已知等腰三角形的两边长分别为 5 ㎝、2 ㎝，则该等腰三角形的周长是（D ）
A．7 ㎝
B．9 ㎝
C．12 ㎝或者 9 ㎝
D．12 ㎝
考查知识点：三角形的基本知识及等腰三角形边的关系：任意两边之和大于第三边，等腰三
角形两腰相等，
因此只能是：5cm，5cm,2cm.
2.一个等腰三角形的一个角是 40°，则它的底角是（D）
A．40° B．50°
C．60°
D．40°或 70°
考查知识点：三角形的内角和及等腰三角形两底角相等：①当 40°是顶角时，底角就是 70°；
②40°就是一个底角.
3.已知△ABC 的三边长分别是 6cm、8cm、10cm，则最长边上的高是（D）
A.2.4cm
B.3cm
C.4cm
D. 4.8cm
提示：设最长边上的高为
1 .6.8 1 .10.h
2
2
h,由题意可得△ ABC 是直角三角形，利用面积相等求，即
解得 h=4.8
3 4.等腰三角形一腰上的高与另一腰的夹角为 30 ，腰长为 6，则其底边上的高是3 或
3.
0
解：①三角形是钝角三角形时，如图 1，∵∠ABD=30°
11 ∴AD= 2 AB= 2 ×6=3，
∵AB=AC，
1
1
∴∠ABC=∠ACB= 2 ∠BAD= 2 (90°-30°)=30°，
∴∠ABD=∠ABC，
∴底边上的高 AE=AD=3；
②三角形是锐角三角形时，如图 2，∵∠ABD=30°
∴∠A=90°-30°=60°，
∴△ABC 是等边三角形，
∴底边上的高为
3 ×6=3 2
3
综上所述，底边上的高是
3
3 或
3
5.到三角形三个顶点的距离相等的点是三角形（B）的交点. A.三个内角平分线 B.三边垂直平分线 C.三条中线 D.三条高 考查的知识点：三角形三边垂直平分线的交点到到三角形三个顶点的距离相等【归纳为：点 到点距离相等，为垂直平分线上的点】还有一个：三角形三个内角平分线的交点到三角形三

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