润滑油箱上为什么要装电加热器？

任务型阅读。回答问题。

    Some things can carry messages, for example, a sign at the bus stop helps you to know which bus to

  take．Signs on the door tell you where to go in or out．Have you ever noticed that there are a lot of

 signs around you and that you receive messages from them all the time?

     People can communicate on many other ways．An artist can use his drawing to tell about beautiful

 mountains, about the blue sea and many other things．Books are written to tell you about all the

 wonderful things in the world and also about people and their ideas．

     Books, magazines, TVs, radios and films all help us lo communicate with others．They all help us to

 know what is going on in the world and what other people are thinking about．

1．What call help you if you want to know which bus to take?

       ___________________________________________

2．What do the signs on the door do?

       _________________________________________

3．People can communicate in many other ways, can't they?

      _________________________________________

4．What can help us to communicate with others?

       ______________________________________

5．What do they help us to do?

      ________________________________________

阅读理解。

     To most of us, school means classes, teachers, schedules, grades and tests. But for the children at

Sudbury Valley School in Massachusetts, school is very different.

     Firstly, there are no lessons. All the children, aged between 4 and 19, do whatever they want. There are

no teachers, only "staff members". The idea behind this is that you do not need to make children learn,

because children want to learn anyway."You do not need to say to a three-year-old, 'Go explore your

environment.' You can't stop them!"says Daniel Greenberg, a founder of the school."But if you make children

do what you want all day… they will lose all taste of learning." At Sudbury Valley School, you will find

children talking, reading, painting, cooking, working on computers, studying French, playing the piano,

climbing trees, or just running around. Two boys spent three years just fishing!

     The other way that Sudbury Valley School is different is that the children can decide the rules. Every

week, there is a school meeting where both children and staff have one vote (投票) each-even the four-year-olds. They decide the school rules, how to spend the school money, and even which staff they want and do not

want anymore.

     When the school first opened in 1968, people said it would never work. But today, the school has 200

students, and 80% of its students go on to college. Even the two boys who went fishing all the time have

successful careers today. One of them is a musician and the other is a computer scientist.

51. What's special about the school?

A. There is nobody but students there.

B. All the students are of the same age.

C. There are no classes for the students.

D. There are no rules in the school.

2. What do the students do in the school?

A. They learn everything there from the staff members.

B. They grow up there without learning anything.

C. They spend all the time with their parents.

D. They do whatever they are interested in.

3. The school seems to believe that children ________.

A. learn best when they are doing what they want

B. are too young to learn anything by themselves

C. can look after themselves without any help

D. can't go to college without any hard work

4. The last paragraph wants to tell us that ________.

A. the writer doesn't like the idea of the school

B. the school is quite successful in its work

C. most of the parents don't believe in the school

D. younger students learn better there than older ones

5. The underlined word career in the last paragraph most probably means ________.

A. family

B. money

C. lifestyle

d. job

白炽灯与日光灯混合电路，总电流应等于白炽灯支路电流与日光灯支路电流的代数和。

英制筛网尺寸的几目是指（）。

参展商参展的主要目的包括（）

A.销售商品，获取订单

B.会见老客户，维持客户关系

C.发展新客户，开拓市场份额

D.展示企业技术、形象，提高企业知名度