About ten men in every hundred suffer from color blindness in some way.Women are luckier.Only about one in two hundred is affected in this matter.So some people say it is safer to be driven by women.

There are different forms of color blindness.]n some cases a man may not be able to see deep red.He may think that red,orange and yellow arc all shades(色调)of green.Sometimes a person cannot tell the difference between blue and green.In rare cases an unlucky man may see everything in shades of green--a strange world indeed.

Color blindness in humans is a strange thing to explain.In our eyes there are millions of very small things called “cones”.These help us to see in a bright light and to tell differences between colors.There are also millions of “rods”,but these are used for seeing when it is nearly dark.They show us shapes but no color.

Some insects have favorite colors.Mosquitoes(蚊子)like blue but do not like yellow.A red light will not attract insects,but a blue lamp will.In a similar way humans also have favorite colors.Yet we are lucky.With the aid of the cones in our eyes We can see many beautiful colors by day,and with the aid of the rods we can see shapes at night.One day we may even learn more about the invisible(看不见的)colors around us.

1.With the help of the cones,we can _________.

A.see in a weak light                                   B.tell different shapes

C.kill mosquitoes                                           D.tell orange from yellow

2.Why do some people say it is safer to be driven by women?

A.Women are more careful.

B.There are fewer color blind women.

C.All of them see everything in shades of green.

D.None of them has trouble in recognizing(识别)colors.

3.This passage is mainly about _________.

A.color and its surprising effects                         B.danger caused by color blindness

C.color blindness                                          D.the invisible colors around us

Do you think there is too much noise in our city? If you live near an airport,you will be unhappy because of a plane often make a loud noise.The sound of planes or heavy vehicles is likely to cause deafness if heard continuously(不断地).

However, most people in our city do not seem to mind noise. They like to enjoy music when they are doing uninteresting jobs.It is a new danger because pop music,when played through powerful amplifiers(放大器),can reach 120 decibels(120分贝的)at a distance of five feet.A continuous noise of over 85 decibels can cause deafness.It was discovered that many young people in America could hear no better than 65-year-old people.

In the past we used to think that only workers in every noisy places would become deaf.For example,when newspapers and books are being printed,the noise level is over 85 decibels,and some of the workers become deaf.Today,however,scientists believe that 10 percent of the workers in Britain are being deafened by the noise.

Sometimes noise of less than 85 decibels can make some people tired and stressed.We all know that too much noise makes life difficult and unpleasant.It can do great harm to people's health and prevent people from working well.Workers in noisy offices are not as efficient(效率高的)as those in quiet offices.Noise makes people less efficient.Can anything be done to reduce or control noise?

In Britain the government has made several laws to reduce noise.Though the government has spent a lot of money in making airports and main roads quieter,many people think that there are still not enough laws.For example,there are no laws to control the noise of machines.In Japan,America and Norway there are such laws.As a result,workers can be given compensation(赔偿)if they become deaf.

1.Some workers become deaf because of ________.

A.hard work                               B.a continuous noise of over 85 decibels

C.powerful amplifiers                       D.uninteresting jobs

2.Noise below the level of 85 decibels ________.

A.can affect some people's moods                     B.cannot do any harm

C.can cause sudden deafness                 D.can make office workers efficient

3.In Britain there are laws to ________.

A.stop workers from becoming deaf                   B.control the noise of machines

C.keep down noise                        D.help deaf workers in need

4.Who can be given compensation if they become deaf?

A.American workers.

B.British workers.

C.Both American workers and British workers.

D.None of the above answers.

Mary picked up a pencil and a piece of paper,saying,“Now,you want to earn money for the autumn camping trip,right?” Tom,her brother,nodded.He wasn’t able to go last year because he hadn’t earned enough money during the summer.This year he came up with a plan.

He made a necklace for his mother that everyone admired.They were surprised to learn that Tom had made it for her.Why not make more necklaces and sell them?

“OK,” said Mary,“The first thing you need to do is to figure out(计算)how much you have now.’’

“I have $20.00 in the bank,and $7.25 in my room,” explained Tom.

“That gives you a total of $27.25,” said Mary,“That is called your capital.The next thing you need to know is how much it will cost you to make each necklace.”

“Well,the pet shop wilt give me all the feathers the birds lose.I'll have to buy the beads(小珠子)and string,” said Tom.

Mary wrote on the piece of paper:

CAPITAL       $27.25

EXPENSES      Feathers      no coat

String for lo necklaces     $2.50

Beads for lo necklaces    + $15.00

Total                    $17.50

“How much do you think you can sell such a necklace for?” asked Mary.

“Hmm,” Tom looked thoughtful and said,“There's a shop in town that sells almost the same kind of necklace for $ 7.50.If I charge(要价)$ 6.00,people will think that's a bargain.”

“OK.If you sell each necklace for $ 6.00,you'll make a good profit(利润)on each then,” said Mary.

“Hurray!” Tom cried,“If I sell 2.0 necklaces,I'll have enough from the profit for the camping trip and $10.00 left over.”

1.Which word best describes Mary?

A.Confident.        B.Generous.        C.Helpful.           D.Outgoing.

2.The underlined word "bargain" in this story means “________”.

A.something sold cheap                                  B.something sold expensive

C.something made at home                             D.something made by children

3.How much would Tom have to spend on the camping trip?

A.$ 47.45.            B.$ 75.               C.$ 85.                     D.$102.25.

4.How did Tom know how much he would have left over after paying for the camping trip?

A,He took the cost of the trip from the profit he would make on 20 necklaces.

B.He added the cost of the trip to the profit he would make on 20 necklaces.

C.He asked Mary for the answer.

D.He took the cost of each necklace from the amount of money he had to begin with.

5.What's the best title for this story?

A.How to Make Necklaces                              B.How to Sell Necklaces

C.How to Make a Plan                                    D.How to Earn Money for a Trip

 0  20023  20031  20037  20041  20047  20049  20053  20059  20061  20067  20073  20077  20079  20083  20089  20091  20097  20101  20103  20107  20109  20113  20115  20117  20118  20119  20121  20122  20123  20125  20127  20131  20133  20137  20139  20143  20149  20151  20157  20161  20163  20167  20173  20179  20181  20187  20191  20193  20199  20203  20209  20217  159627 

违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com

精英家教网