光华中学投资126万元新贱一座教学楼,比计划节省八分之一,计划投资多少万元?用方程,按照等量关系写

防止+不 ——双重否定表肯定
应为：为防止今后 再发生类似的悲剧,……
改为：为防止今后再发生类似的悲剧,光华中学制定了严厉的规章制度

设甲班有x人,乙班有y人．
由题意可得 6+9（x-1）=13+8（y-1）,300＜6+9（x-1）＜400,
即 ,
因为x为整数,
所以x=34,35,36,37,38,39,40,41,42,43,44．
又因为y也是整数,所以x是8的倍数,
所以x=40,y=44．
所以总人数是x+y=84．
答：甲、乙两班学生总人数共是84人．
这题我们老师刚讲过,

One possible version:
Good morning, everyone,
I am Li Hua from Guanghua Middle School. The topic of my speech is “Let’s Ride Bicycles”.
It is known to us that cars bring us a lot of problems. Air pollution, the most serious one, has make it hard for humans to live. And with more and more people buying private cars, traffic becomes heavier and heavier. Therefore, it’s time for us to choose another transport, that is, cycling.
There are many good reasons to ride bicycles. Firstly, compared to cars, bicycles are much cheaper to buy. What’s more, bicycles are more environmentally friendly than cars, because they hardly make noises. Cycling has become a new trend around the world, a good way of energy saving and low-carbon life. Last but not least, cycling is an excellent way to keep fit and live longer. By riding bicycles, you can cut down your risk of heart attacks, high blood pressure and other illnesses.
So I think, riding bicycles actually has great effects on us. Let’s ride bicycles from today on!
That’s all. Thank you!


试题分析：这是一篇给材料作文。本文所给材料比较简略，故动笔前要认真阅读材料，组织写作内容，不可遗漏要点，并适当发挥。写作中注意从两方面进行叙述，首先介绍当今的交通堵塞问题，然后分三点介绍骑行车的好处。根据材料内容可知本文主要是一般现在时态，注意时态语时间状语的搭配及主谓一致问题。写作中适当使用连词，注意上下文联系紧密，符合逻辑关系。
点评:该题型主要考查学生的语言表达能力，在写作中根据所给提示和语言信息，不遗漏要点，可以适当发挥。做到表达清楚，语法正确，上下文连贯

Dear sir or madam,
Thanks for your time first,let me introduce myself to you .my name is liming .And i am a 17 years old student in guanghua middle school.i am a outgoing student and responsible student who likes children.In school ,my favorite subject is English.what is more, I lived in the United kingdom.so my English spoken is good and i have the paper to show my english level
I like not only english but also art. Last year ,in the school paintingcompetition i won the first prize. That something about me.thanks for your time again.

设车上有X个座位
(X-3)*(1-10%)+7=X
X=43

(1)八年级(1)班平均分=(a-b)/m 八年级(2)班平均分=(a+b）/2m【(a-b)/m】/ 【(a+b）/2m】=(a-b)/【2(a+b）】=（a-b）/2(2)1 第三个分式的分母应该是y的三次方吧.(-x^5/y) / (x^3/y)= -x^2/y(x^7/y^3) / (-x^5/y)= -x^2/y(-x^9/y^4) / (x^7/y^3)= -x^2/y 后一个分式都是前一个分式的（-x^2/y）倍2 第七个分式为 x^15/y^7