摘要: What can the parrot say?A. Good morning to you! B. Nice to meet you! C. Happy Birthday to you!

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When the traffic lights turn red, we will stop driving a car or crossing a street. Why is red used for traffic lights instead of other colors?
As we know, scattering(散射) happens when light goes through the air. For the same media(媒质), if the wavelength islong, the scattering will be short. If the wavelength is short, then the scattering will be long.
Of all lights we can see red has the longest wavelength, so the scattering is the weakest. That means the red light travels far. In fact, it travels farther on rainy days.
Using the red light can help drivers in farther areas sec the lights. It helps drivers stow down or stop in lime. If drivers don't see the red light until they are close, they may not be able to stop the car in time. An accident may happen Red can also excite people. We can act more quickly when we see the color red. In a word, red lights help drivers stop in time and help prevent accidents.
【小题1】 When the traffic lights turn ______, we will stop driving a car.
A. red    B green     C. yellow
【小题2】According to the passage, the scattering of the red light is the _______.
A. longest    b. weakest       C. farthest
【小题3】 The underlined word "wavelength" means________ in Chinese.
A.波浪        B.光波      C.波长
【小题4】 What can the red light help drivers do?
A. It can help drivers in farther areas see the lights.
b. It can help drivers slow down or stop in time.
C.A and b
【小题5】Which of the following is the best title?
A. Why do accidents happen
b. How does the red light travel
C. Why do we use red traffic lights
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Dogs like living with people. A dog can be a very good friend. He can do a lot of things for people.

Some dogs help people to look after sheep, other dogs help them to find lost (丢失的)children. And some of the dogs can help the blind(盲人)do things.

Many years ago there was a ver dog. His name was Seeing Eye dog. Now we can see this kind of dogs all over the world. They are working for the blind. The Seeing Eye dog is strong ,good and easy to train(训练).He helps the blind to walk from place.

Before a dog becomes a Seeing Eye dog, he must go to a training school for about three months. First the dog has to learn to sit or stay when he hears the trainer’s call. In his next lesson the dog learns to make his trainer across busy streets.

The dog has many things to learn. And in every lesson he must to do one thing again and again many times.

At the end of the training schooled must take tests. When he passes the tests, the Seeing Eye dog will do things by himself.

Now he can help blind people. The new master(主人)may be a man, a woman, or even a child. It takes the dog and his blind master about a month to learn to work and live together.

1.We can see the Seeing Eye dog           .

A.only in the country

B.only in small cities

C.all over the world

D.only on the busy street

2.What can the Seeing Eye dog do?

A.Look after sheep

B.Help blind people

C.Find lost children

D.Train blind people

3.How long will it take the dog and his blind master to learn to work and live together?

A.One year

B.Five years

C.About a month

D.A week

 

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Dogs like living with people. A dog can be a very good friend. He can do a lot of things for people. Some dogs help people to look after sheep, other dogs help them to find lost children. And some of the dogs can help the blind (盲人) do things.
Many years ago there was a very good dog. His name was Seeing Eye dog. Now we can see this kind of dogs all over the world. They are working for the blind.
The Seeing Eye dog is strong, good and easy to train(训练). He helps the blind to walk from place to place.
Before a dog becomes a Seeing Eye dog, he must go to a training school for about three months. First the dog has to learn to sit or stay when he hears the trainer’s call. In his next lesson the dog learns to make his trainer across busy streets
The dog has many things to learn. And in every lesson he must learn to do one thing again and again for many times.
At the end of the training school he must take tests. When he passes the tests, the Seeing Eye dog will do the things by himself.
Now he can help blind people. The new master may be a man, a woman, or even a child. It takes the dog and his blind master about a month to learn to work and live together.
【小题1】We can see the Seeing Eye dog _______.

A.only in the countryB.only in small cities
C.all over the worldD.only on the busy street
【小题2】What can the Seeing Eye dog do?
A.Look after sheepB.Help blind people
C.Find lost childrenD.Train blind people
【小题3】If you want a dog to become a Seeing Eye dog, you must let him ________.
A.go to a training schoolB.go to a middle school
C.go to an evening schoolD.go to a children school
【小题4】First the dog has to learn to sit or stay __________.
A.when he hears the telephone callB.when he hears another dog’s call
C.when he hears the master’s callD.when he hears the trainer’s call
【小题5】How long will it take the dog and his blind master to learn to work and live together?
A.one yearB.five yearsC.about a monthD.one week

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