第一篇：人教版 英語 八下 復習-U10

10單元短語

1、到中午為止________________________

2、在富蘭克林湖_______________________

3、瀏覽_______________________

4、閑談_______________________

5、看起來像_______________________

6、在周末_______________________

7、去游泳_______________________

8、有點熱_______________________

9、度過愉快的一天_______________________

10、在電梯中_______________________

11、走路上學_______________________

12、排隊等候_______________________

13、感謝信_______________________

14、出現、發生、來到____________________

15、相處_______________________

16、至少_______________________

17、最多_______________________

18、告訴某人關于某事___________________

19、在電視上_______________________20、周五晚上的比賽_____________________

21、過得愉快_______________________

22、在周六的晚上_______________________

23、對某人友好_______________________

24、想要（3個）_______________________

25、群體的一部分_______________________

26、做某事有困難_______________________

27、…票_______________________

28、與某人一起去_______________________

29、想起_______________________30、你的真誠的朋友_____________________

31、在這個時候_______________________

32、小心去做某事_______________________ 10單元句型

1、跟我說說你自己。_________________________________________________________

2、你認為這個學校真么樣？__________________________________________________

3、成為學校一名新成員并不容易。_____________________________________________

4、在周六晚上我玩的很開心。__________________________________________________

5、非常感謝你邀請我。_______________________________________________________

6、現在我感覺自己向集體中的一員了。__________________________________________

7、在你到來之前，我一直在很辛苦的找這所學校。_______________________________

8、當我們看到黑襪子隊贏比賽時，我會想到你的。_________________________________

9、至少沒有下雨。________________________________________________________

10、他的確如此__________________________________________________________

11、我希望如此。_________________________________________________________

12、你認為到中午時雨會停嗎？____________________________________________

13、它們的價格是真低，不是嗎？___________________________________________

14、這條路線很慢，不是嗎？_______________________________________________ 話題作文：

假如你是Carol，昨天你參加了朋友Vera在家里舉行的生日聚會，請根據提示給她寫一封感謝信。

提示：

1、Vera的父母及朋友很友好。

2、蛋糕好吃，飯可口。

3、影碟很好看，你很喜歡。

____________________________________________________________________________

第二篇：英語八下U10重點

八下U10

1.重點詞匯 1.看起來像下雨 2.很擁擠

3.祝一天玩得痛快

4.瀏覽書籍、報紙、雜志、相冊 5.穿過一條繁忙的街道 6.聊天

7.到中午之前為止

在中午

8.價格高、價格低、以低的價格 用低的聲音

9.告訴我你自己的事情、10.今天是好天氣，不是嗎？ 11.隊伍很慢，不是嗎？ 12.慢的火車 13.在周六晚上

在四月一號的早晨 14.感覺像

想做什么 15.對某人友好 16.做某事有困難 17.幫助我學數學

幫助吧掃衛生和做飯 幫助(某人)做某事 18.更容易

使做某事更容易 19.相處

相處得好

和某人相處的好、在某方面進展的順利20.當我們觀看黑襪子隊贏的比賽

當什么的時候 入鄉隨俗

21.喜歡遇見你的家人 22.因為，，感謝 23.小心做某事

小心不做某事 小心

照看、照料 24.至少 25.交通很忙 26.一封感謝信 27.在公交車上 28.在公交車站 29.在弗蘭克林湖旁 30.在周末

1.look like rain 2.be very crowded 3.have a good day

4.4.look through books/newspapers/magazine/photo album 5.5.cross a busy street 6.6.small talk7.7.by noon8.at noon

9.8.high price/ low price

at a low pricein a low voice

9.tell me about yourself

10.This is great weather ,isn’t it? 11.This line is slow , isn’t it ? 12.slow train

13.on Saturday night

on the morning of April 1 14.feel like

.feel like doing =would like to do =want to do sth 15.be friendly to sb

16.have a hard time doing sth17help me with my math

help with cleaning and cooking

help(sb)with doing =help(sb)to do the =help(sb)do 18 a lot easier

make it a lot easier to do sth19.get along(on)get along(on)well

get along(on)well with sb /sth

20.as we watch the Black Socks win the gameas +從句

Do as the Romans do.21.enjoy meeting your family

22.Thanks /Thank you for n./doing sth23.be careful to do sthbe careful not to do sht

be careful =take care= look outtake care of ，，=look after 24.at least

25.The traffic is busy/heavy.26.a thank—you note27.on a/the bus28.at the bus stop29.at Franklin Lake

30.at the weekend =at weekends

31。15路公交車31.the No.15 bus

32.我希望公交車很快來

33.它確實這樣

對，，有把握一定能做某事

確信

答語：當然了

把什么能清楚

確保

34.每天走著去學校

35.對我有點熱

36.和某人說再見

和某人說對不起

和某人說早安、晚安

37.某物花費某人多少錢

買某物花了某人多少錢

某人買某物付了多少錢

某人花多少時間和錢做某事

做某事花了某人多少時間

38.在派對上

在會議上

39.周五晚上的比賽

今天的作業

40.一次很棒的派對

41.玩得痛快

42.在學校作為一名新生有時是不容易的43.認識某人（延續性動詞）、非延續性動詞

44.一些女生

45.你給我們放映的視頻

46.集體的一份子

47.很抱歉，，48真的很高興做某事

49.讓某人做某事

50.觀看某人正在做某事、觀看某人做某事的過程（或曾做過某事——

51.贏得比賽

贏了對方（贏了他）

52.指給我學校的路

指路

給某人看什么東西

53.對什么擅長

對，，有益處

對，，好 54.像你這樣的朋友

55.和我一起去

56.早離開了

57.舉行家宴

32.I hope the bus comes soon.33.It sure is.be sure of /about，，be sure to do sth ] be sure that ，，, Sure=Surely =Certainly=Of course make sure of n/ doingmake sure that ，， 34.walk to school every day35.a little hot for me36.say goodbye to sbsay sorry to sbSsy good morning/night to sb37.sth cost sb monyIt cost sb money to do shtSb pay money for sthSb spend money time/money(in)doing sth /on shtIt take sb time to do sth38.at the partyAt the meeting39.Friday night’s game today’s homework40.a great party41.have a wonderful time42.Sometimes it isn’t easy being the new kid at school.43.know sbget to know sb 44.some of the girls 45.the vedio you showed46.part of the group47I am sorry(that)，， 48.be really happy to do sth49.ask sb to do sth50.watch sb doing sth /watch sb do sth

win the gamebeat ，，(beat him)52.show me the schoolshow the wayshow sb sth =show sth to sb53.be good atbe good for ，，be good with sb(善于處理之間的關系)be good to sb 54.friends like you55.go with you56.leave early57.have a family dinner

58.舉行他90歲生日派對 59.我和tom

60.我們兩個都喜歡體育我們兩個都會游泳我們兩個都將去

我們兩個都完成了作業我們兩個都是學生 Both反義詞

Both A and B 的反義詞 61.暑假在度假

在一個假期里去某地度假 一個三天的假期 62.在這個時間

63.難道你不這么認為嗎？(否定疑問句)(代詞)這么，，以至于，，(副詞)不和，，一樣（原級比較否定句）(副詞)他已經完成作業了。我也完成了(連詞

他很用功，所以他總考第一(副詞, 因果關系 一般般

那么聰明的一個男孩

64.在學校餐廳里 65.等10分鐘

58.have his 90th birthday party 59.Tom and I

60.We both like sports.We can both swim.We will both go there.We have both finished our homework.We are both students.neither

neither A nor B

61.summer holiday =summer holidayson holidayin a holiday

go to sp for a holiday = have a holiday in spa holiday of three days62.at this time

63.Don’t you think so ？so ，，that ，,not so ，，as

He has finished his homework.So have IHe works hard , so he always wins the first.Just so so.so clever a boy

64.at the school dining room 65.wait for 10 minutes

第三篇：人教版英語八下八下U10教案

人教版八年級下冊第十單元英語教案 Unit 10 I’ve had this bike for three years.常考短語

1.how long 多久，多長時間

2.have a yard sale 舉行庭院拍賣會

3.give away 捐贈；贈送

4.not … any more 不再…… 5.Welcome to … 歡迎到……

6.a bit 一點兒，稍微

7.board game 棋類游戲

8.check out 察看；觀察

9.a bread maker 面包機

10.grow up 長大

11.clear out 收拾，整理

12.a lot of 許多

13.no longer 不再；不復

14.at first 起初

15.for example 例如

16.a rain and railway set 一套軌道火車

17.as for…至于……

18.give up 放棄

19.to be honest 說實在的 20.at least 至少

21.on weekends 在周末

22.once or twice year 一年一兩次

23.millions of 數百萬的 24.search for 尋找

25.according to 依據；按照

26.across from 在……的對面

27.in one’s opinion 依……看

28.in order to 為了

經典句型

1.It is +adj.(+for sb.)+to do sth.(對某人來說)做某事是…… 2.want to do sth.想要做某事

3.love doing sth.喜歡做某事

4.decide to do sth.決定做某事

5.have been in + 地點

在某處待了多久

6.hope to do sth.希望做某事

7.one of + the+ 形容詞最高級+可數名詞復數

最······之一

8.used to do sth.過去常做某事

9.need to do sth.需要做某事 知識詳解：.--How long have you had that bike there?--I have had it for three years 辨析：how long, how soon, how often, how far How long 多久，多長（時間）。對時間段提問，如：for+時間段；since+過去的時間點。

e.g.--How long have you worked in Beijing?

--For five years.How soon 多久以后。對in+時間段提問，常用于一般將來時，其答語常用―in+時間段。

e.g.–How soon will Mr.Li be back?

--In a week.How often 多久一次，對頻率提問，其答語為：once（twice/…）+時間段，always，usually等。

e.g.--How often do you exercise?

--Once a day.How far 多遠，對距離提問，其答語是表距離的內容。

e.g.--How far is it from here to your school?

--Three kilometers.2.辨析：for 與since

for其后只能接表示一段時間的名詞性短語

e.g.I have lived in this city for five years.我在這座城市居住了5年了 since 其后接表示―時間點的短語或從句（過去時），也可以接一段時間+ago，常用于完成時態； 還用于句型：It is +時間段+since+一般過去時的句子。表示過去某個時間發生并持續到說話時的動作或狀態。

e.g.It is two years since I came to China.自從我到中國以來已經兩年了。

She has worked here for five years.=She has worked here since five years ago.她在這兒工作5年了。

3.Amy thinks it’s hard to sell her old things.艾米認為賣掉她的舊東西很難。

It’s +adj.(+for sb.)to do sth.意為（對某人來說）做某事時……的，it 是形式主語，真正主語是后面的動詞不定式。

e.g.It’s important for un to learn English well.學好英語對于我們來說是很重要的。

4.The stories inside may be a bit old, but they’re still interesting.a bit 意為一點兒，稍微，修飾形容詞或副詞，相當于 a little；

a bit of +不可數名詞，a little直接加不可數名詞。

e.g.There is a bit of/a little water in the bottle.瓶子里有點兒水。

not a bit =not at all 意為一點也不

not a little =very 意為非常

e,g.She is not a bit happy.她一點兒也不快樂。

He is not a little tired.=He is very tired.他非常累。

5.We have decided to each sell five things that we no longer use.no longer 意為―不再；不復，有時可用 not …any longer 或 not … anymore 替換。如：

He no longer lives here.(= He doesn’t live here anymore/any longer.)他不再住這兒了。

6.My daughter was more understanding, although she also felt sad to part with certain toys.part with 放棄、交出，part v.離開，分開

e.g.Don’t part with your dream.不要放棄你的夢想。

7.Nowadays, millions of Chinese leave the countryside to search for work in the cities.Search用作不及物動詞時，意為搜索；搜查。短語search for 意為搜尋，找尋。

e.g.He is searching for his sunglasses.他正在找他的太陽鏡。

【拓展】作及物動詞，意為在······搜查或搜查。

e.g.They searched the forest for the lost child.他們在森林里尋找那個走失的小孩。

8.a 46-year-old husband and father意為一位46歲的丈夫和父親，相當于a husband and father of 46years old.four-year-old 是一個復合形容詞，特點一是數詞、名詞、形容詞之間要用連字符連接，二是數詞后的名詞用單數形式。

e.g.Tom is a 10-year-old boy.= Tom is a boy of 10 years old.湯姆是一個10歲的男孩。

Lily is an 8-year-old girl.莉莉是一個8歲的女孩

【拓展】另一種類似的復合形容詞作定語的結構是：數詞+連字符+名詞，或數詞+名詞的所有格。

e.g.a two-month holiday=a two months’ holiday 一個為期兩個月的假期。Ten-minute walk/drive/ride=ten minutes’

walk/drive/ride 步行/開車/騎車10分鐘的路程

9.Many people like Zhong Wei regard with great interest how their hometowns have changed.regard 及物動詞，意為將······認為；把······視為。

常用短語regard…as…意為將······視為······；把······當做······，as 為介詞，其后接名詞或代詞。

e.g.I regard you as my best friend.我把你當做我最好的朋友。

We regard him as our brother.我們把他當成兄弟看待。

10.consider 動詞，意為考慮，=think about，后跟名詞，代詞，動名詞，賓語從句或疑問詞+不定式。

e.g.Please consider my suggestion.請考慮我的建議。

I am considering changing my job.我正在考慮換份工作。He has never considered how to solve the problem他從未考慮過如何解決那個問題。

【拓展】在與動詞連用時，只能用動名詞形式的動詞或短語有：

consider ―考慮

enjoy ―喜愛

practice―練習

keep（on）―繼續（一直）

mind ―介意

finish―完成have fun ―高興

feel like ―想要

look forward to ―盼望

can’t help ―禁不住

give up ―放棄

歌訣：喜歡錯過別介意，完成愉快勤練習，禁不住考慮想放棄

11.hold

hold及物動詞，意為―擁有；抓住，過去式和過去分詞均為held

e.g.He holds a major share in the company.他持有該公司的大部分股份。

He is holding a book in her hand.她手里正拿著一本書。

【拓展】hold用作及物動詞，還可意為舉行；主持，相當于have e.g.They will hold a meeting to discuss this problem tomorrow.對比現在完成時和一般過去時的不同: 現在完成時

表示從過去已經開始持續到現在的動作或狀態，可以和表示―從過去某一時刻延續到現在的一段時間狀語‖連用，如for + 時間段、since + 過去時間點、since + 過去時的從句、since + 一段時間 + ago。且for與since引導的時間狀語可以相互轉換。

e.g.My uncle has worked at this factory for ten years.= My uncle has worked at this factory since ten year ago.I’ve lived here since 1990． 自從1990年以來我就住在這里。

I haven’t seen him for three years.我三年沒有看見他了。

She’s been at this school since five years ago.自從五年前以來她就在這個學校。

1.這本書我買了5年了。

I have bought the book for five years.()

I’ve had the book for five years.（）2.你哥哥參軍多長時間了？

How long has your brother joined the army?()How long has your brother been in the army/been a soldier?（）

非延續性動詞和延續性動詞之間的轉換

1.轉換為相應的延續性動詞，用于現在完成時。

2.轉化為―be + 形容詞/副詞/介詞/名詞

borrow/lend---keep

begin---be on

leave---be away buy---have 單項選擇

1.--____ have you been married？

--For twenty years.A.How far

B.How often

C.How long

D.How soon 2.--I often have hamburgers for lunch.--You’d better not.It’s bad for you ____ too much junk food.A.eat

B.to eat

C.eating

D.ate 3.My best friend Tom is ____ honest boy.You can believe him.A.a

B.an

C.the

D./

4.– Is Mr.Smith still in Shanghai?

--Yes, he ____ there for two months.A.has been

B.has gone

C.has been to

D.has gone to 5.I don’t believe that this ___boy can paint such a nice picture.A.five years old B.five-years-old C.five-year-old 6 Look!She’s standing ___ the ten children.A.among B.between C.of D.from

7.--Can you give me some information about vacation trips?

--Why not _________ going to Hainan Island?

A.consider

B.mind C.keep

D.think

8.Mr.Jack ______ China for several years.A.has been to B.has come to

C.has been in

D.came to

9、He has _______ been to Shanghai , has he ?

Ａ.already Ｂ.never Ｃ.ever Ｄ.still

10、The famous writer _____ one new book in the past two years.Ａ.is writing Ｂ.was writing Ｃ.wrote Ｄ.has written

11、Zhao Lan ______already ______in this school for two years.Ａ.was studying Ｂ.will study

Ｃ.has studied Ｄ.are studying

12、We ______ Xiao Li since she was a little girl.Ａ.know Ｂ.had known Ｃ.have known Ｄ.knew

13、Harry Potter is a very nice film.I_______ it twice.Ａ.will see Ｂ.have seen Ｃ.saw Ｄ.see

14.—______ you ___ your homework yet ?

—Yes.I _____ it a moment ago.Ａ.Did;do;finished

Ｂ.Have;done;finished

Ｃ.Have;done;have finished

Ｄ.will;do;finish 15.There are two books on the desk, but ____of them is interesting。

A．none

B．neither

C．both

D．all

16.—Have you ever _______ to the Summer Palace, Lily?

—No, I __________.A.gone, hasn’t B.gone, haven’t C.been , haven’t D.been, hasn’t 17.I have ________ the book for three days.A．borrowed

B．lent

C．bought

D．kept

18.Alice is ______an American ________a German.She is an Australia.A.both;and

B.either;or

C.neither;nor

D.not;but 19.Mike doesn’t know French.And_________

.A.so do I

B.so am I

C.neither do I

D.neither am I

20.John _______ Beijing.He is still there.A.has been to

B.has gone to

C.go to

D.goes to

21.--May I speak to John?

--Sorry, he ______ Japan.But he _______ in two days.A.has been to;will come back

B.has gone to;will be back

C.has been in;would come back

D.has gone to;won` t come back 22..Neither you nor I_______ a teacher.A.is

B.are

C.am

D.be 23.The Smiths______ China for three years.A.have come B.have been to C.have been in D.have come to 24..―When_______his grandpa______‖.― Three years ago.‖

A.has;died

B.is;dead

C.did;die

D.is;died 25.There is not ___________in today’s newspaper.A.nothing interesting

B.interesting something C.interesting

D.anything interesting 26.Simon is _________ honest boy.Now he is studying at ________ university.A.a;an

B.an;a

C.the;a

D.a;the

27.I’m looking after Tom today.He’s been in my house _________ 8:00 this morning.A.at

B.for

C.since

D.till

28.----How long have you ________ here?---For two days.I _________ here the day before yesterday.A.been;came

B.come;came

C.came;came

D.been;come 29.---I don’t know where to go this summer vacation.---Why not _________ visiting Huanggang? There are many places of interest here.A.suggest

B.wonder

C.consider

D.regard 30.Oh, no!It’s raining.We can’t go skating on the square.___________!

A.What a shame

B.Well done

C.What a surprise

D.How wonderful 31.---Did you go to Kenli during the Peach Blossom Destival?(桃花節)---Yes, the flowers are beautiful.Bees were flying _________ them.A.in

B.among

C.between

D.through 32.---Did you borrow the comic book from the library?---Yes, I ________ it for three days.I’ll return it this afternoon.A.borrowed

B.kept

C.have borrowed

D.have kept 33.----How is your grandma?---She’s fine.She used to _________ TV at home after supper.But now she is used to _______ out for a walk.A.watch;go

B.watching;go

C.watching;going

D.watch;going

二．綜合填空A.從方框中選擇合適的詞并用其適當形式填空。Make, hold, part with, consider, search for, go, Check 1.I __________ my paper carefully before I handed it in.2..So far I ______

quiet a few friends here.3.Nowadays, millions of Chinese leave the countryside ______ work in the cities.4.―Where’s Li Ming?‖ ―He ________ to the teacher’s office.‖ 5.I ________ changing my job these days.6.They ________ a meeting to discuss this problem tomorrow.7.My daughter was more understanding, although she also felt sad _______ certain toys.

第四篇：人教八下數學 《二次根式》復習教案2個

二次根式復習課

教學目標

1．使學生進一步理解二次根式的意義及基本性質，并能熟練地化簡含二次根式的式子；

2．熟練地進行二次根式的加、減、乘、除混合運算．

教學重點和難點

重點：含二次根式的式子的混合運算．

難點：綜合運用二次根式的性質及運算法則化簡和計算含二次根式的式子．

教學過程設計

一、復習

1．請同學回憶二次根式有哪些基本性質？用式子表示出來，并說明各式成立的條件．

指出：二次根式的這些基本性質都是在一定條件下才成立的，主要應用于化簡二次根式．

2．二次根式的乘法及除法的法則是什么？用式子表示出來．

指出：二次根式的乘、除法則也是在一定條件下成立的．把兩個二次根式相除，計算結果要把分母有理化．

3．在二次根式的化簡或計算中，還常用到以下兩個二次根式的關系式：

4．在含有二次根式的式子的化簡及求值等問題中，常運用三個可逆的式子：

二、例題

例1

x取什么值時，下列各式在實數范圍內有意義：

分析：

(1)題是兩個二次根式的和，x的取值必須使兩個二次根式都有意義；

(3)題是兩個二次根式的和，x的取值必須使兩個二次根式都有意義；

(4)題的分子是二次根式，分母是含x的單項式，因此x的取值必須使二次根式有意義，同時使分母的值不等于零．

x≥-2且x≠0．

解因為n2-9≥0，9-n2≥0，且n-3≠0，所以n2=9且n≠3，所以

例3

分析：第一個二次根式的被開方數的分子與分母都可以分解因式．把它們分別分解因式后，再利用二次根式的基本性質把式子化簡，化簡中應注意利用題中的隱含條件3-a≥0和1-a＞0．

解：因為1-a＞0，3-a≥0，所以a＜1，|a-2|＝2-a．

(a-1)(a-3)=[-(1-a)][-(3-a)]=(1-a)(3-a)≥0．

這些性質化簡含二次根式的式子時，要注意上述條件，并要闡述清楚是怎樣滿足這些條件的．

問：上面的代數式中的兩個二次根式的被開方數的式子如何化為完全平方式？

分析：先把第二個式子化簡，再把兩個式子進行通分，然后進行計算．

解

注意：

所以在化簡過程中，例6：

分析：如果把兩個式子通分，或把每一個式子的分母有理化再進行計算，這兩種方法的運算量都較大，根據式子的結構特點，分別把兩個式子的分母看作一個整體，用換元法把式子變形，就可以使運算變為簡捷．

a+b＝2(n+2)，ab=(n+2)2-(n2-4)＝4(n+2)，三、課堂練習

1．選擇題：

A．a≤2　　B．a≥2　　C．a≠2　　D．a＜2

A．x+2

B．-x-2　　C．-x+2　　D．x-2

A．2x

B．2a　　C．-2x　　　D．-2a

2．填空題：

4．計算：

四、小結

1．本節課復習的五個基本問題是“二次根式”這一章的主要基礎知識，同學們要深刻理解并牢固掌握．

2．在一次根式的化簡、計算及求值的過程中，應注意利用題中的使二次根式有意義的條件(或題中的隱含條件)，即被開方數為非負數，以確定被開方數中的字母或式子的取值范圍．

3．運用二次根式的四個基本性質進行二次根式的運算時，一定要注意論述每一個性質中字母的取值范圍的條件．

4．通過例題的討論，要學會綜合、靈活運用二次根式的意義、基本性質和法則以及有關多項式的因式分解，解答有關含二次根式的式子的化簡、計算及求值等問題．

五、作業

1．x是什么值時，下列各式在實數范圍內有意義？

2．把下列各式化成最簡二次根式：

二次根式復習課

教學目標

1．使學生進一步理解二次根式的意義及基本性質，并能熟練地化簡含二次根式的式子；

2．熟練地進行二次根式的加、減、乘、除混合運算．

教學重點和難點

重點：含二次根式的式子的混合運算．

難點：綜合運用二次根式的性質及運算法則化簡和計算含二次根式的式子．

教學過程設計

一、復習

1．請同學回憶二次根式有哪些基本性質？用式子表示出來，并說明各式成立的條件．

指出：二次根式的這些基本性質都是在一定條件下才成立的，主要應用于化簡二次根式．

2．二次根式的乘法及除法的法則是什么？用式子表示出來．

指出：二次根式的乘、除法則也是在一定條件下成立的．把兩個二次根式相除，計算結果要把分母有理化．

3．在二次根式的化簡或計算中，還常用到以下兩個二次根式的關系式：

4．在含有二次根式的式子的化簡及求值等問題中，常運用三個可逆的式子：

二、例題

例1

x取什么值時，下列各式在實數范圍內有意義：

分析：

(1)題是兩個二次根式的和，x的取值必須使兩個二次根式都有意義；

(3)題是兩個二次根式的和，x的取值必須使兩個二次根式都有意義；

(4)題的分子是二次根式，分母是含x的單項式，因此x的取值必須使二次根式有意義，同時使分母的值不等于零．

x≥-2且x≠0．

解因為n2-9≥0，9-n2≥0，且n-3≠0，所以n2=9且n≠3，所以

例3

分析：第一個二次根式的被開方數的分子與分母都可以分解因式．把它們分別分解因式后，再利用二次根式的基本性質把式子化簡，化簡中應注意利用題中的隱含條件3-a≥0和1-a＞0．

解：因為1-a＞0，3-a≥0，所以a＜1，|a-2|＝2-a．

(a-1)(a-3)=[-(1-a)][-(3-a)]=(1-a)(3-a)≥0．

這些性質化簡含二次根式的式子時，要注意上述條件，并要闡述清楚是怎樣滿足這些條件的．

問：上面的代數式中的兩個二次根式的被開方數的式子如何化為完全平方式？

分析：先把第二個式子化簡，再把兩個式子進行通分，然后進行計算．

解

注意：

所以在化簡過程中，例6：

分析：如果把兩個式子通分，或把每一個式子的分母有理化再進行計算，這兩種方法的運算量都較大，根據式子的結構特點，分別把兩個式子的分母看作一個整體，用換元法把式子變形，就可以使運算變為簡捷．

a+b＝2(n+2)，ab=(n+2)2-(n2-4)＝4(n+2)，三、課堂練習

1．選擇題：

A．a≤2　　B．a≥2　　C．a≠2　　D．a＜2

A．x+2

B．-x-2　　C．-x+2　　D．x-2

A．2x

B．2a　　C．-2x　　　D．-2a

2．填空題：

4．計算：

四、小結

1．本節課復習的五個基本問題是“二次根式”這一章的主要基礎知識，同學們要深刻理解并牢固掌握．

2．在一次根式的化簡、計算及求值的過程中，應注意利用題中的使二次根式有意義的條件(或題中的隱含條件)，即被開方數為非負數，以確定被開方數中的字母或式子的取值范圍．

3．運用二次根式的四個基本性質進行二次根式的運算時，一定要注意論述每一個性質中字母的取值范圍的條件．

4．通過例題的討論，要學會綜合、靈活運用二次根式的意義、基本性質和法則以及有關多項式的因式分解，解答有關含二次根式的式子的化簡、計算及求值等問題．

五、作業

1．x是什么值時，下列各式在實數范圍內有意義？

2．把下列各式化成最簡二次根式：

第五篇：八下英語作文復習3

八下英語作文復習：

英語作文考試時注意的問題

1．認真審題立意

對命題作文必須認真審題，注意格式，對自由作文必須立好意（觀點）。

2.注意

（1）寫好開篇句，（2）用好時態

（3）用好連接詞，如：and，but ,although, however, if , when , while等。注意段落間、句子間的連貫性，思路清晰，文字連貫。

（4）有一兩句好句子提升作文質量。

（5）結尾句和開篇句相互呼應。

3.字體工整，卷面整潔是留給改卷老師的第一個好印象。

Unit 1

第一篇 :The future in Zhengzhou

一定要注意將來時的運用。

I am fromzhengzhou.It’s a beautiful city with greentrees.I think in ten years, the road will be wider and cleaner.There will be more buses ,treesand less pollution.The people inZhengzhou will be much happier.第二篇： life in the future

What will the life be likein the future ?I think my life will be more interesting and wonderful in the future.many things will be done by robots , they can also help do some cleaning ,washing and cooking.We don't need to sit in the classroom and listen to teachers.We can study throughcomputers.We will be able to see a doctor and do some shopping on computers.I think it will come true.Unit 2

本單元的考點：回復求助信。當人家遇到困難時，給別人真誠的建議。

There are a lot of things you could do.(你有很多可以做的事情)

I think you should(could)??來組織整篇文章。常見的建議有：(1)you should say sorry.(2)you should write a letter.(3)you could buy him a gift.(4)you should have a talk with him to communicate better.(5)you should find a part-time job.(6)you could give him a ticket to a ball game.(7)you should talk about your problems with your parents.(8)you should learn to relsx.最后，別忘了在信的結尾寫上 Goodluck.祝人家好運。

范文：How do you get on well with your classmates?

Today, many students say they don’t know how to get on well with their classmates.They are in trouble.Now, I will give you some advice.First of all, believe everyone.Believing is very important.Believe others and you can be believed.Secondly, give a hand when your classmates need help.Last, whenever being on time is very important.If you follow the advice above, I believe you can get on well with everyone.Unit 3

本單元的考點：用一般過去時態敘述曾經發生的事情

第一篇 An unforgettable（難忘的）experience---A Happy Thing

Last Saturday my classmates and I went to the old people’s home to help the old people.After we got there , we began to clean the rooms and wash clothes for the old people.We also talked to them.After that we played games with them.The old people were very happy.They laughed and laughed.And they said “Thank you” again and again.Though we were tired , we were also glad.Because we helped other people.I will not forget the happy thing.第二篇My happiest day

It was my birthday yesterday.I 've been 13 years old.My parents hold a birthday party for me.And bought me new and beautiful clothes and books as presents.My friends were invitied to the party.They also played games together.We really enjoyed ourselves.I was quite happy.Unit 4

本單元重點是：用間接引語（賓語從句）闡述成績報告單

1.主句： 過去時，從句也用：過去時（2.主句一般時，從句根據情景用任何時態。

A letter to Mike

Dear Mike,How time flies!I had the tests last week and got my report card today.Some marksare good, some are bad.I had a really hard time with physics, and I wasn’t surprised to find that my worse report was from my physics teacher, he said I was a lazy student, which isn’t true.It’s just that I find physics really diffcult.My physics’s mark is 55.Another disappointing result was in math.My math teacher said I could do better.The good news is that my math teacher said I was hard-working.My math’s mark is 80.My English teacher said I was good at English and reading.The PE teacher said I ran fastest in school.She said I was hard-working.As for Chinese, I did OK this time..And what about you?

Unit 5

本單元重點：if 條件句，主句用一般將來時，從句用一般現在時

If I have a lot of money

If I have a lot of money, I will do something important.My dream will come true.Of course, I can do a lot with money.I’ll help the old.I’ll help the poor.Most of all, I’ll help these poor children who can’t go to school.I hope they will not only change themselves in the future with the knowledge, but also change the world around them.At the same time, I think I’ll help my parents enjoy their lives.Ln a word, I can do a lot of wonderful things and make the people around ushappier and happier.Unit 6 $ 9

本單元重點：巧妙運用現在完成時、一般過去時、一般現在時和一般將來時等時態敘述過去發生的事情。

An Unforgettable Experience

Have you ever been to another city for a trip ? I have been to many places before.butDalian is my favourite.This summer holiday, I went to Dalian with my family.We got there by air.Dalian is a very beautiful and modern city.On the bus, we could see all kinds of buildings which were great.In the morning, we got to the hotel where we lived.After breakfast, we beganour travel.First we took the bus to the Sea Park.There are so many different kinds of fishes that I couldn't believe my eyes.We also saw the show of dolphins.Then we had lunch in a restaurant.The seafood which was very famous in China was delicious.After lunch we went swimming.The sea was blue and beach was golden.We all enjoyed ourselves in the sea.Finally we went back the hotel where we lived.We had a happy day.In this trip, we also went to some places which were interesting and famous in Dalian.Several days later, we left Dalian.On our way home, we were very happy.This was the reason why we didn't feel tired.In all, we had a good holiday.I think I will go there again some day.同學們，以下是不可不了解的發散性（自由）作文，請掌握他們。

寫一篇保護環境的英語演講稿。

提示：

1.在購物時用布袋子替代塑料袋;

2.盡可能地再利用使用過的課本;

3.離開教室應關燈;

4.最好走路或騎自行車上學;

5.簡述理由：保護環境，減少污染，節約能源等

參考作文：

What Can We Do for the Environment You know,The environmentis becomingworse and worse.Many trees are cutting down, some animals are getting less and less.In order to live a better life, we need to protect our world.The first thing we can do is to use cloth bags instead of plastic(塑料）bags when we go shopping.It helps to protect the environment.The second thing we can do is to reuse(再利用)the old textbooks as possible as we can.We should also never forget to turn off the lights when we leave the classrooms in order to save energy（能源）.What’s more（而且）, itwill be better if we walk or ride a bike toschool.We should try our best tomake pollution less and less.In fact, even the simplest everyday activities(日常活動)can have an influenceon(對?有影響)the environment.I believe we can make the world a better place to live in.(I believe our world will be more and more beautiful)

Thank you for your listening!

My summer holiday plans（My summer holiday）Hello, everyone.I’m Li Hua.It’s nice to speak about what we can do for the environment。

1.summer holiday is coming, I need to make a holiday plan.First, I plan to finish my homework in two weeks.Then I would like togo traveling abroad.It is really fun to meet foreign friends and learn foreign culture.At last, I think it'S necessary for me to go over my lessons in order not to forget what I have learnt.I think I will have a wonderful holiday.2.My summer holiday is coming soon.My family are going to Beijing, the capital of China.There are many places of interest.For example, the Great Wall is one of the most famous places in the world.And we are going to visit other famous places, like the Palace Museum, the Summer Palace and so on.Now I am going over my English and study English harder and harder.I hope I can travel all over the world.I think my dream will come true some day in the future.My English learning

Some students study English by reading English magazines or newspapers, and some of them are interested in watching English programs on TV.In my opinion, every day, we should insist on reading the textbooks and learning words by heart.Listening to English tapes and keeping diaries are very useful, too.Singing English songs is also a good way for us to improve our oral English.What’s more we should often speak English.No pains, no gains.I’m sure we’ll make great progress if we keep on working hard at it.Love around me

I think love is always around me.When I am in trouble at school, my classmates and teachers often help me.When I am upset, my parents often encourage me.I feel very thankful when they give me their love.I should show my love to them.When I am happy, I should share my happiness with them.When someone is in trouble, I should try my best to help him.Let's show our love to the people who love us.A terrible earthquake

A terrible earthquake happened in Japan on March 11, 2011.The earthquake center was in the northeastern of Japan.It caused a huge tsunami and killed many people.The worst thing was that it caused a terrible nuclear leak.It is said that(據說）it was the worst onein Japan and in the world , it was the fifth worst after 1900.However , the Japanese are trying their best to fight against the terrible natural disaster(和自然災難做斗爭）.We are sure they can get success.I want to be a player(my dream)

Everyone has a dream.But I think my dream is to be a football star when I grow up.I liked playing football when I was a child.No matter what the weather is like, I often play football with my friends on the playground after school.I like Ronaldo best.Now I will do my best to study hard in the school.I believe my dream will come true in the future.At that time, I am not only proud of my parents, but also proud of myself.Now I am still a middle school student.I must try my best to work hard at my lessons.I think my dream will come true some day in the future if I work hard.