请根据以要点写一篇简单介绍美国的文章。注意不要逐句翻译，字数100～120。

    1）美国位于北美洲的中部，西毗邻太平洋，东毗邻大西洋。南边与墨西哥接壤，北边与加拿大相连。

    2）美国的首都华盛顿位于美国的东部。   

    3）美国最大的城市是纽约，它位于美国的东海岸，有“大苹果”之称。联合国总部大楼就坐落在这里。

    4）美国由50个州组成，国土总面积为936万平方公里。

    5）美国有约23亿的人口，其中工人占大多数。

    6）美国最早的居民为印第安人。由于美国是一个移民国家，故有“大熔炉”之称。

生词：移民immigrant    大熔炉a melting pot 

此题要求改正所给短文中的错误。对标有题号的每一行作出判断：如无错误，在该行右边横线上画一个勾（√）；如有错误（每行只有一个错误），则按下列情况改正：

    此行多一个词：把多余的词用斜线（＼）划掉，在该行右边横线上写出该词，并也用斜线划掉。

    此行缺一个词：在缺词处加一个漏字符号（∧），在该行右边横线上写出该加的词。

    此行错一个词：在错的词下划一横线，在该行右边横线上写出改正后的词。

注意：原行没有错的不要改。

    This afternoon we had the PE lesson．The teacher taught           1．________

us how to practise high jump．The bell rung and we came              2．________

to the playground in line．After warm up exercises, the teacher           3．________

told me the way of jumping and then gave us an example．              4．________

We followed the teacher one after another．Soon was my               5．________

mm and I felt a bit more nervous．I failed for the first time but           6．________

I was not discouraged．I kept on thinking the teacher's words           7．________

and practising．At last I tried to jump over the pole．From              8．________

this class I come to realize one can succeed whether he                        9．________

has perseverance just as the old saying goes, "Where there is a                   10．________

will, there is a way．"

In the United States the most popular form of folk dancing since the earliest days has been square dancing．In early times, when men and women worked in groups to build a barn（building where animals are kept） or harvest crops, they danced when the work was done．The music came from a violin from the most part, but if there was no one to play an instrument, placcing was used to produce the rhythm （loud and soft sounds made in a certain order） by which to dance．The early settlers danced in a store, in a barn, or in a farm kitchen．

A square is formed by four couples who stand facing the center of the square．Each couple stands on one side of the square, the boy on the left and girl on the right．

    The caller is an important part of the dance since he tells the dancers which steps to do．If the dancers do not know the steps, he teaches them．It takes time for a learner to be a good caller, and good callers are always in demand．

    These are the names of some of the steps the dancers do．Form a square; Circle; Honour your partner; Promenade （walk about slowly）, Swing your partner; Form a star．There are many more．As the caller tells the dancers what to do next, they move to form the pattern he calls．

Large or small numbers of people can dance at one time．Sometimes 800 or 1,000 people may be dancing at the same time．Or there may be only one square of eight people．

    Tumecoses are worn by some who square dance．This makes the dancing more colorful to watch．The tumecoses vary from place to place．Women often were full skirts of various colors with a pretty blouse．Men have colored shirt and western trousers which they．wear only when square dancing, In some country areas, everyone wears his best clothes．

    Today in all parts of the United States you will find some school, club, or other group that is square-dancing for fun．

1．In the past, people danced ________．

    A．when they were doing their work                    B．before they did their work

    C．after they finished their work'                D．before a big party

2．In the first paragraph, the word "plac" means ________．

A．hit the hands together to make a sound 

B．a kind of thing like radios

C．shout at the top of one's voice        

D．knock something to make a sound

3．Which of the following statements is true?

    A．The caller is the most beautiful person in square dancing．

    B．The caller knows everything about square dancing．

    C．It is not difficult to learn to be a good caller．

    D．The caller play an important part in square dancing．

4．If 1,000 people dance at the same time, how many squares can be formed?

    A．Only on big square．                      B．1,000 squares．

    C．More than 100 squares．                   D．Less than 100 squares．

5．In the sixth paragraph, the word "tumecoses" means ________．

    A．special clothes                            B．a kind of hat with flowers on it

    C．a ring worn on the finger                   D．clothes worn when working

Memory, they say, is a matter of practice and exercise．If you have the wish and really make a conscious （自觉的） effort, then you can quite easily improve your ability （能力） to remember things．But even if you are successful, there are times when your memory seems to play tricks on you．

Sometimes you remember things that really did not happen．One morning last week, for example, I got up and found that I had left the front door unlocked all night, yet I clearly remember locking it carefully the night before．

Memory "tricks" work the other way as well．Once in a while you remember not doing something and then find out that you did．One day last month, for example, I was sitting in a barber （理发师） shop waiting for my turn to get a haircut, and suddenly I realized that I had got a haircut two clays before at the barber shop across the street from my office．

    We always seem to find something funny and amusing （有趣的） in incidents （事件） caused by people's  forgetfulness or absent-mindedness．Stories about absent-minded professors have been told for years, and we never get tired of hearing new ones．Unfortunately, however, absent-mindedness is not always funny．There are times when "tricks" of our memory can cause us great trouble．

1．lf you want to have a good memory ________．

A．you should force yourself to remember things

    B．you should make a conscious effort of practice and exercise

    C．you should try to remember as many poems as possible

    D．you should try hard to remember things

2．Which of the following statements is true according to the passage?

    A．One night the writer forgot to lock the front door

    B．One night the writer forgot having locked the front door

    C．The writer remembered to lock the door

    D．The writer remembered unlocking the front door

3．From the sentence "We never get fired of hearing new ones．"we can infer that ________．

    A．we enjoy hearing new stories about absent-mindedness of professors

    B．we don't want to know anything more about absent-mindedness of professors

    C．we will never get tired of listening to new stories about absent-mindedness

    D．absent-mindedness happens not only to professors but to many other people

4．In the passage, the writer seems to tell you ________．

    A．forgetting things happens to learned people

    B．always forgetting things is understandable

    C．forgetting things at times is natural

    D．ways to protect yourself from memory tricks

5．The best title for this passage is _________．

A．How to Get a Good Memory                    

B．"Tricks" of Memory

C．Stories about Forgetfulness and Absent-mindedness 

D．Get Rid of Absent-mindedness

Bar Code

    All the packets you buy in a supermarket carry a bar code．This code is scanned （扫描） by laser light and the brand and product names are given to the customer with the price．The people running the store can keep a continuous check of how many packets of each product and of size are on the shelves．Special supermarket checkouts are needed to read the code．

    The code is a mixture of bar and space width．It is printed onto the package and cannot be written by hand．

A bar code showing the Australian Product Number （APN） symbol, made up of vertical （直的） stripes and spaces．

    The Australian Product Number, which you see in supermarkets, is made up of 13 digits （numbers）．For example: 9300663271733 means:

93 ＝ country code．Australia is 93, New Zealand is 94．

00663 ＝ manufacture's code--all products from this maker have this code number．

27173 ＝ product number and size tells what the product is, and the size of the article．

3 ＝ check digit--from the addition of some previous digits．This check's to make sure that the code has been read correctly．

1．Bar Codes are made up of ________．

A．13 equally spaced bars              

B．13 numbers matching 13 even bas

C．a mixture of bars and space widths    

D．a mixture of equal spaced, varying width bars

2．It is NOT possible to ________．

    A．have Bar Codes for all supermarket packets

    B．make Bar Codes, using more than one zero

    C．buy goods using foreign Bar Codes

    D．draw your own Bar Codes

3．The following Bar Code informs the supermarket manager that the ________．

9312345678907

    A．product has no APN symbol

    B．goods came from New Zealand

    C．product was produced in Australia

    D．particular goods are almost out of date．