第一篇：人教版 英语 八下 复习-U10
10单元短语
1、到中午为止________________________
2、在富兰克林湖_______________________
3、浏览_______________________
4、闲谈_______________________
5、看起来像_______________________
6、在周末_______________________
7、去游泳_______________________
8、有点热_______________________
9、度过愉快的一天_______________________
10、在电梯中_______________________
11、走路上学_______________________
12、排队等候_______________________
13、感谢信_______________________
14、出现、发生、来到____________________
15、相处_______________________
16、至少_______________________
17、最多_______________________
18、告诉某人关于某事___________________
19、在电视上_______________________20、周五晚上的比赛_____________________
21、过得愉快_______________________
22、在周六的晚上_______________________
23、对某人友好_______________________
24、想要（3个）_______________________
25、群体的一部分_______________________
26、做某事有困难_______________________
27、…票_______________________
28、与某人一起去_______________________
29、想起_______________________30、你的真诚的朋友_____________________
31、在这个时候_______________________
32、小心去做某事_______________________ 10单元句型
1、跟我说说你自己。_________________________________________________________
2、你认为这个学校真么样？__________________________________________________
3、成为学校一名新成员并不容易。_____________________________________________
4、在周六晚上我玩的很开心。__________________________________________________
5、非常感谢你邀请我。_______________________________________________________
6、现在我感觉自己向集体中的一员了。__________________________________________
7、在你到来之前，我一直在很辛苦的找这所学校。_______________________________
8、当我们看到黑袜子队赢比赛时，我会想到你的。_________________________________
9、至少没有下雨。________________________________________________________
10、他的确如此__________________________________________________________
11、我希望如此。_________________________________________________________
12、你认为到中午时雨会停吗？____________________________________________
13、它们的价格是真低，不是吗？___________________________________________
14、这条路线很慢，不是吗？_______________________________________________ 话题作文：
假如你是Carol，昨天你参加了朋友Vera在家里举行的生日聚会，请根据提示给她写一封感谢信。
提示：
1、Vera的父母及朋友很友好。
2、蛋糕好吃，饭可口。
3、影碟很好看，你很喜欢。
____________________________________________________________________________
第二篇：英语八下U10重点
八下U10
1.重点词汇 1.看起来像下雨 2.很拥挤
3.祝一天玩得痛快
4.浏览书籍、报纸、杂志、相册 5.穿过一条繁忙的街道 6.聊天
7.到中午之前为止
在中午
8.价格高、价格低、以低的价格 用低的声音
9.告诉我你自己的事情、10.今天是好天气，不是吗？ 11.队伍很慢，不是吗？ 12.慢的火车 13.在周六晚上
在四月一号的早晨 14.感觉像
想做什么 15.对某人友好 16.做某事有困难 17.帮助我学数学
帮助吧扫卫生和做饭 帮助(某人)做某事 18.更容易
使做某事更容易 19.相处
相处得好
和某人相处的好、在某方面进展的顺利20.当我们观看黑袜子队赢的比赛
当什么的时候 入乡随俗
21.喜欢遇见你的家人 22.因为，，感谢 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 26.一封感谢信 27.在公交车上 28.在公交车站 29.在弗兰克林湖旁 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 +从句
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路公交车31.the No.15 bus
32.我希望公交车很快来
33.它确实这样
对，，有把握一定能做某事
确信
答语：当然了
把什么能清楚
确保
34.每天走着去学校
35.对我有点热
36.和某人说再见
和某人说对不起
和某人说早安、晚安
37.某物花费某人多少钱
买某物花了某人多少钱
某人买某物付了多少钱
某人花多少时间和钱做某事
做某事花了某人多少时间
38.在派对上
在会议上
39.周五晚上的比赛
今天的作业
40.一次很棒的派对
41.玩得痛快
42.在学校作为一名新生有时是不容易的43.认识某人（延续性动词）、非延续性动词
44.一些女生
45.你给我们放映的视频
46.集体的一份子
47.很抱歉，，48真的很高兴做某事
49.让某人做某事
50.观看某人正在做某事、观看某人做某事的过程（或曾做过某事——
51.赢得比赛
赢了对方（赢了他）
52.指给我学校的路
指路
给某人看什么东西
53.对什么擅长
对，，有益处
对，，好 54.像你这样的朋友
55.和我一起去
56.早离开了
57.举行家宴
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(善于处理之间的关系)be good to sb 54.friends like you55.go with you56.leave early57.have a family dinner
58.举行他90岁生日派对 59.我和tom
60.我们两个都喜欢体育我们两个都会游泳我们两个都将去
我们两个都完成了作业我们两个都是学生 Both反义词
Both A and B 的反义词 61.暑假在度假
在一个假期里去某地度假 一个三天的假期 62.在这个时间
63.难道你不这么认为吗？(否定疑问句)(代词)这么，，以至于，，(副词)不和，，一样（原级比较否定句）(副词)他已经完成作业了。我也完成了(连词
他很用功，所以他总考第一(副词, 因果关系 一般般
那么聪明的一个男孩
64.在学校餐厅里 65.等10分钟
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：人教版英语八下八下U10教案
人教版八年级下册第十单元英语教案 Unit 10 I’ve had this bike for three years.常考短语
1.how long 多久，多长时间
2.have a yard sale 举行庭院拍卖会
3.give away 捐赠；赠送
4.not … any more 不再…… 5.Welcome to … 欢迎到……
6.a bit 一点儿，稍微
7.board game 棋类游戏
8.check out 察看；观察
9.a bread maker 面包机
10.grow up 长大
11.clear out 收拾，整理
12.a lot of 许多
13.no longer 不再；不复
14.at first 起初
15.for example 例如
16.a rain and railway set 一套轨道火车
17.as for…至于……
18.give up 放弃
19.to be honest 说实在的 20.at least 至少
21.on weekends 在周末
22.once or twice year 一年一两次
23.millions of 数百万的 24.search for 寻找
25.according to 依据；按照
26.across from 在……的对面
27.in one’s opinion 依……看
28.in order to 为了
经典句型
1.It is +adj.(+for sb.)+to do sth.(对某人来说)做某事是…… 2.want to do sth.想要做某事
3.love doing sth.喜欢做某事
4.decide to do sth.决定做某事
5.have been in + 地点
在某处待了多久
6.hope to do sth.希望做某事
7.one of + the+ 形容词最高级+可数名词复数
最······之一
8.used to do sth.过去常做某事
9.need to do sth.需要做某事 知识详解：.--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，多长（时间）。对时间段提问，如：for+时间段；since+过去的时间点。
e.g.--How long have you worked in Beijing?
--For five years.How soon 多久以后。对in+时间段提问，常用于一般将来时，其答语常用―in+时间段。
e.g.–How soon will Mr.Li be back?
--In a week.How often 多久一次，对频率提问，其答语为：once（twice/…）+时间段，always，usually等。
e.g.--How often do you exercise?
--Once a day.How far 多远，对距离提问，其答语是表距离的内容。
e.g.--How far is it from here to your school?
--Three kilometers.2.辨析：for 与since
for其后只能接表示一段时间的名词性短语
e.g.I have lived in this city for five years.我在这座城市居住了5年了 since 其后接表示―时间点的短语或从句（过去时），也可以接一段时间+ago，常用于完成时态； 还用于句型：It is +时间段+since+一般过去时的句子。表示过去某个时间发生并持续到说话时的动作或状态。
e.g.It is two years since I came to China.自从我到中国以来已经两年了。
She has worked here for five years.=She has worked here since five years ago.她在这儿工作5年了。
3.Amy thinks it’s hard to sell her old things.艾米认为卖掉她的旧东西很难。
It’s +adj.(+for sb.)to do sth.意为（对某人来说）做某事时……的，it 是形式主语，真正主语是后面的动词不定式。
e.g.It’s important for un to learn English well.学好英语对于我们来说是很重要的。
4.The stories inside may be a bit old, but they’re still interesting.a bit 意为一点儿，稍微，修饰形容词或副词，相当于 a little；
a bit of +不可数名词，a little直接加不可数名词。
e.g.There is a bit of/a little water in the bottle.瓶子里有点儿水。
not a bit =not at all 意为一点也不
not a little =very 意为非常
e,g.She is not a bit happy.她一点儿也不快乐。
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 意为―不再；不复，有时可用 not …any longer 或 not … anymore 替换。如：
He no longer lives here.(= He doesn’t live here anymore/any longer.)他不再住这儿了。
6.My daughter was more understanding, although she also felt sad to part with certain toys.part with 放弃、交出，part v.离开，分开
e.g.Don’t part with your dream.不要放弃你的梦想。
7.Nowadays, millions of Chinese leave the countryside to search for work in the cities.Search用作不及物动词时，意为搜索；搜查。短语search for 意为搜寻，找寻。
e.g.He is searching for his sunglasses.他正在找他的太阳镜。
【拓展】作及物动词，意为在······搜查或搜查。
e.g.They searched the forest for the lost child.他们在森林里寻找那个走失的小孩。
8.a 46-year-old husband and father意为一位46岁的丈夫和父亲，相当于a husband and father of 46years old.four-year-old 是一个复合形容词，特点一是数词、名词、形容词之间要用连字符连接，二是数词后的名词用单数形式。
e.g.Tom is a 10-year-old boy.= Tom is a boy of 10 years old.汤姆是一个10岁的男孩。
Lily is an 8-year-old girl.莉莉是一个8岁的女孩
【拓展】另一种类似的复合形容词作定语的结构是：数词+连字符+名词，或数词+名词的所有格。
e.g.a two-month holiday=a two months’ holiday 一个为期两个月的假期。Ten-minute walk/drive/ride=ten minutes’
walk/drive/ride 步行/开车/骑车10分钟的路程
9.Many people like Zhong Wei regard with great interest how their hometowns have changed.regard 及物动词，意为将······认为；把······视为。
常用短语regard…as…意为将······视为······；把······当做······，as 为介词，其后接名词或代词。
e.g.I regard you as my best friend.我把你当做我最好的朋友。
We regard him as our brother.我们把他当成兄弟看待。
10.consider 动词，意为考虑，=think about，后跟名词，代词，动名词，宾语从句或疑问词+不定式。
e.g.Please consider my suggestion.请考虑我的建议。
I am considering changing my job.我正在考虑换份工作。He has never considered how to solve the problem他从未考虑过如何解决那个问题。
【拓展】在与动词连用时，只能用动名词形式的动词或短语有：
consider ―考虑
enjoy ―喜爱
practice―练习
keep（on）―继续（一直）
mind ―介意
finish―完成have fun ―高兴
feel like ―想要
look forward to ―盼望
can’t help ―禁不住
give up ―放弃
歌诀：喜欢错过别介意，完成愉快勤练习，禁不住考虑想放弃
11.hold
hold及物动词，意为―拥有；抓住，过去式和过去分词均为held
e.g.He holds a major share in the company.他持有该公司的大部分股份。
He is holding a book in her hand.她手里正拿着一本书。
【拓展】hold用作及物动词，还可意为举行；主持，相当于have e.g.They will hold a meeting to discuss this problem tomorrow.对比现在完成时和一般过去时的不同: 现在完成时
表示从过去已经开始持续到现在的动作或状态，可以和表示―从过去某一时刻延续到现在的一段时间状语‖连用，如for + 时间段、since + 过去时间点、since + 过去时的从句、since + 一段时间 + ago。且for与since引导的时间状语可以相互转换。
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． 自从1990年以来我就住在这里。
I haven’t seen him for three years.我三年没有看见他了。
She’s been at this school since five years ago.自从五年前以来她就在这个学校。
1.这本书我买了5年了。
I have bought the book for five years.()
I’ve had the book for five years.（）2.你哥哥参军多长时间了？
How long has your brother joined the army?()How long has your brother been in the army/been a soldier?（）
非延续性动词和延续性动词之间的转换
1.转换为相应的延续性动词，用于现在完成时。
2.转化为―be + 形容词/副词/介词/名词
borrow/lend---keep
begin---be on
leave---be away buy---have 单项选择
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?(桃花节)---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．综合填空A.从方框中选择合适的词并用其适当形式填空。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：人教八下数学 《二次根式》复习教案2个
二次根式复习课
教学目标
1．使学生进一步理解二次根式的意义及基本性质，并能熟练地化简含二次根式的式子；
2．熟练地进行二次根式的加、减、乘、除混合运算．
教学重点和难点
重点：含二次根式的式子的混合运算．
难点：综合运用二次根式的性质及运算法则化简和计算含二次根式的式子．
教学过程设计
一、复习
1．请同学回忆二次根式有哪些基本性质？用式子表示出来，并说明各式成立的条件．
指出：二次根式的这些基本性质都是在一定条件下才成立的，主要应用于化简二次根式．
2．二次根式的乘法及除法的法则是什么？用式子表示出来．
指出：二次根式的乘、除法则也是在一定条件下成立的．把两个二次根式相除，计算结果要把分母有理化．
3．在二次根式的化简或计算中，还常用到以下两个二次根式的关系式：
4．在含有二次根式的式子的化简及求值等问题中，常运用三个可逆的式子：
二、例题
例1
x取什么值时，下列各式在实数范围内有意义：
分析：
(1)题是两个二次根式的和，x的取值必须使两个二次根式都有意义；
(3)题是两个二次根式的和，x的取值必须使两个二次根式都有意义；
(4)题的分子是二次根式，分母是含x的单项式，因此x的取值必须使二次根式有意义，同时使分母的值不等于零．
x≥-2且x≠0．
解因为n2-9≥0，9-n2≥0，且n-3≠0，所以n2=9且n≠3，所以
例3
分析：第一个二次根式的被开方数的分子与分母都可以分解因式．把它们分别分解因式后，再利用二次根式的基本性质把式子化简，化简中应注意利用题中的隐含条件3-a≥0和1-a＞0．
解：因为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．
这些性质化简含二次根式的式子时，要注意上述条件，并要阐述清楚是怎样满足这些条件的．
问：上面的代数式中的两个二次根式的被开方数的式子如何化为完全平方式？
分析：先把第二个式子化简，再把两个式子进行通分，然后进行计算．
解
注意：
所以在化简过程中，例6：
分析：如果把两个式子通分，或把每一个式子的分母有理化再进行计算，这两种方法的运算量都较大，根据式子的结构特点，分别把两个式子的分母看作一个整体，用换元法把式子变形，就可以使运算变为简捷．
a+b＝2(n+2)，ab=(n+2)2-(n2-4)＝4(n+2)，三、课堂练习
1．选择题：
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．填空题：
4．计算：
四、小结
1．本节课复习的五个基本问题是“二次根式”这一章的主要基础知识，同学们要深刻理解并牢固掌握．
2．在一次根式的化简、计算及求值的过程中，应注意利用题中的使二次根式有意义的条件(或题中的隐含条件)，即被开方数为非负数，以确定被开方数中的字母或式子的取值范围．
3．运用二次根式的四个基本性质进行二次根式的运算时，一定要注意论述每一个性质中字母的取值范围的条件．
4．通过例题的讨论，要学会综合、灵活运用二次根式的意义、基本性质和法则以及有关多项式的因式分解，解答有关含二次根式的式子的化简、计算及求值等问题．
五、作业
1．x是什么值时，下列各式在实数范围内有意义？
2．把下列各式化成最简二次根式：
二次根式复习课
教学目标
1．使学生进一步理解二次根式的意义及基本性质，并能熟练地化简含二次根式的式子；
2．熟练地进行二次根式的加、减、乘、除混合运算．
教学重点和难点
重点：含二次根式的式子的混合运算．
难点：综合运用二次根式的性质及运算法则化简和计算含二次根式的式子．
教学过程设计
一、复习
1．请同学回忆二次根式有哪些基本性质？用式子表示出来，并说明各式成立的条件．
指出：二次根式的这些基本性质都是在一定条件下才成立的，主要应用于化简二次根式．
2．二次根式的乘法及除法的法则是什么？用式子表示出来．
指出：二次根式的乘、除法则也是在一定条件下成立的．把两个二次根式相除，计算结果要把分母有理化．
3．在二次根式的化简或计算中，还常用到以下两个二次根式的关系式：
4．在含有二次根式的式子的化简及求值等问题中，常运用三个可逆的式子：
二、例题
例1
x取什么值时，下列各式在实数范围内有意义：
分析：
(1)题是两个二次根式的和，x的取值必须使两个二次根式都有意义；
(3)题是两个二次根式的和，x的取值必须使两个二次根式都有意义；
(4)题的分子是二次根式，分母是含x的单项式，因此x的取值必须使二次根式有意义，同时使分母的值不等于零．
x≥-2且x≠0．
解因为n2-9≥0，9-n2≥0，且n-3≠0，所以n2=9且n≠3，所以
例3
分析：第一个二次根式的被开方数的分子与分母都可以分解因式．把它们分别分解因式后，再利用二次根式的基本性质把式子化简，化简中应注意利用题中的隐含条件3-a≥0和1-a＞0．
解：因为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．
这些性质化简含二次根式的式子时，要注意上述条件，并要阐述清楚是怎样满足这些条件的．
问：上面的代数式中的两个二次根式的被开方数的式子如何化为完全平方式？
分析：先把第二个式子化简，再把两个式子进行通分，然后进行计算．
解
注意：
所以在化简过程中，例6：
分析：如果把两个式子通分，或把每一个式子的分母有理化再进行计算，这两种方法的运算量都较大，根据式子的结构特点，分别把两个式子的分母看作一个整体，用换元法把式子变形，就可以使运算变为简捷．
a+b＝2(n+2)，ab=(n+2)2-(n2-4)＝4(n+2)，三、课堂练习
1．选择题：
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．填空题：
4．计算：
四、小结
1．本节课复习的五个基本问题是“二次根式”这一章的主要基础知识，同学们要深刻理解并牢固掌握．
2．在一次根式的化简、计算及求值的过程中，应注意利用题中的使二次根式有意义的条件(或题中的隐含条件)，即被开方数为非负数，以确定被开方数中的字母或式子的取值范围．
3．运用二次根式的四个基本性质进行二次根式的运算时，一定要注意论述每一个性质中字母的取值范围的条件．
4．通过例题的讨论，要学会综合、灵活运用二次根式的意义、基本性质和法则以及有关多项式的因式分解，解答有关含二次根式的式子的化简、计算及求值等问题．
五、作业
1．x是什么值时，下列各式在实数范围内有意义？
2．把下列各式化成最简二次根式：
第五篇：八下英语作文复习3
八下英语作文复习：
英语作文考试时注意的问题
1．认真审题立意
对命题作文必须认真审题，注意格式，对自由作文必须立好意（观点）。
2.注意
（1）写好开篇句，（2）用好时态
（3）用好连接词，如：and，but ,although, however, if , when , while等。注意段落间、句子间的连贯性，思路清晰，文字连贯。
（4）有一两句好句子提升作文质量。
（5）结尾句和开篇句相互呼应。
3.字体工整，卷面整洁是留给改卷老师的第一个好印象。
Unit 1
第一篇 :The future in Zhengzhou
一定要注意将来时的运用。
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
本单元的考点：回复求助信。当人家遇到困难时，给别人真诚的建议。
There are a lot of things you could do.(你有很多可以做的事情)
I think you should(could)„„来组织整篇文章。常见的建议有：(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，别忘了在信的结尾写上 Goodluck.祝人家好运。
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
本单元的考点：用一般过去时态叙述曾经发生的事情
第一篇 An unforgettable（难忘的）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
本单元重点是：用间接引语（宾语从句）阐述成绩报告单
1.主句： 过去时，从句也用：过去时（2.主句一般时，从句根据情景用任何时态。
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
本单元重点：if 条件句，主句用一般将来时，从句用一般现在时
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
本单元重点：巧妙运用现在完成时、一般过去时、一般现在时和一般将来时等时态叙述过去发生的事情。
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.同学们，以下是不可不了解的发散性（自由）作文，请掌握他们。
写一篇保护环境的英语演讲稿。
提示：
1.在购物时用布袋子替代塑料袋;
2.尽可能地再利用使用过的课本;
3.离开教室应关灯;
4.最好走路或骑自行车上学;
5.简述理由：保护环境，减少污染，节约能源等
参考作文：
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(日常活动)can have an influenceon(对„有影响)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(据说）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(和自然灾难做斗争）.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.
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