Scientists have helped people understand the dangers the earth is facing.As people live on the earth, we should be fully ready to deal with the dangers.If we do not pay more attention to the problems caused by air pollution, our earth may no longer be a healthy place for plants, animals, and people to live.

　　　 Cleaning up the air is a job that all countries must work on.The problems caused by air pollution can be solved, but a lot of work needs to be done.Governments around the world are beginning to work together to lower the levels of dangerous gases in the atmosphere (大气层).If this can be done well, the ozone layer (臭氧层) can rebuild itself, global warming can be controlled, and acid rain can be reduced.

　　　 In 1967, the government of the United States passed the Clean Air Act.More parts were added to the act in 1970, 1977 and 1990.As a result of these laws, cars now must reduce the amounts of harmful gases.Power factories must use “clean coal” methods to reduce acid?rain gases they produce.

　　　 In 1970, the Environmental Protection Agency (EPA) was set up.The EPA's job is to make sure that the environmental laws are being followed and to find out new dangers and offer solutions.The first Earth Day was also ce?lebrated in 1970.

　　　 While it is very important to address with air on a global scale, each person can also do something to protect the earth.Here are some things you can do every day：

(1)Turn down the heat and air conditioning.

(2)Use the dishwasher only when there are full of dishes.

(3)Practice the 3 Rs: recycle, reuse, and reduce.

(4)Plant a tree.

(5)Walk or ride your bike.

(　　)6.If we don't care about ________ problems, our earth may no longer be a healthy place.

A.air pollution B.water pollution

C.noise pollution　 D.sea pollution

(　　)7.Every country should ________ to solve the problems caused by air pollution.

A.rebuild the ozone layer　　　 B.clean up the air

C.produce harmful gases D.reduce acid?rain gases

(　　)8.All the things the EPA can do is to ________.

A.make more laws 　　　　　 　B.find out new dangers

C.protect the environment D.plant trees

(　　)9.The Clean Air Act was passed ________ by the American government.

A.In 1967　 B.In 1970 　C.In 1977 D.In 1978

(　　)10.In our daily life, we can do something to protect the earth by ________.

A.using more cars B.riding the bikes

C.cutting down trees　 D.turning up the heat

Most of my classmates don't like to talk with their parents, but I am __________ them. I love to talk with my parents.

　　A. the same as　　　　B. different from　　C. interested in D. angry with

What do you do if you're stranded（处于困境的）on a lonely island? Surely you need to find a way to get in touch with the outside world. Your best chance of doing this is to draw the attention of a passing plane.

　　Body signals（信号）

　　Pilots from different countries understand body signals if they have the correct training. When you wave your arms up and down in a straight line, it means "yes". When you point downwards and swing your arm from side to side, it means "no". If you want the pilot to know that it's safe to land, push your hands out in front of you and bend（弯曲）your knees. If you want to say that it's not safe to land, put your arms in the air and move them to one side.

　　Smoke signals

　　The smoke from a fire can be seen from far away, so it's a good way to draw attention. If the weather is dry, it isn't hard to start a fire. Remember, however, that fires can be very dangerous if they get out of control. Never light a fire unless you're sure that it can't spread. If the ground is dark, light smoke can be seen more easily. Green grass and leaves produce light smoke.

　　Ground-to-air signals

　　It's a good idea to build some signals, too. Use large pieces of wood to make the symbols(标记). If you can't find any wood, use earth. Some useful symbols are:

　　F "I need food and water."

　　II "I need medicine."

　　I "I am badly hurt."

　　X" I am unable to move from here."

　　Pilots' replies

　　If the pilot lowers the plane's wings from side to side, this means "message received and understood". (At night, the pilot flashes the plane's green lights.) If the pilots flies the plane in a clockwise circle, this means "message received but not understood".(At night, the pilot flashes the plane's red lights.)

However, there is no signal which means "message not received". Why not?

1. Which picture means "it's not safe land"?

2. What can we learn from the passage?

　　A. Swinging your arm from side to side means "yes".

　　B. If the ground is dark, light smoke can't be seen.

　　C. If you need some medicine, make a symbol "II".

　　D. The pilots make replies with a blue light at night.

　　3. What is the passage mainly about?

　　A. The explanation of building signals on an island.

　　B. The importance of making signals on an island.

　　C. Ways of sending out signals on a lonely island.

D. Ways of receiving signals from a lonely island

Once upon a time, there lived a rich man. He had a servant (仆人). He and the servant loved wine and good food very much. Each time the rich man left his home; the servant would drink the wine and eat up all the nice food in the house. The rich man knew what his servant did, but he had never caught his servant doing that.

　　One morning, when he left home, he said to the servant, “Here are two bottles of poison (毒药) and some nice food in the house. You must take care of them.” With these words, he went out.

　　But the servant knew that what the rich man had said was untrue. After the rich man was away from his home, he enjoyed a nice meal. Because he drank too much, he was drunk and fell to the ground. When the rich man came back, he couldn’t find his food and his wine. He became very angry. He woke the servant up. But the servant told his story very well. He said a cat had eaten up everything. He was afraid to be punished(惩罚), so he drank the poison to kill himself.

1.In the story, _______ liked wine and good food very much.

    A. the rich man 　　B. the servant 　　C. both A and B 　　D. neither A and B

2.The rich man knew that it was _______ that drank the wine and ate up all the nice food.

A. the cat 　　 　　B. himself 　　　    C. nobody 　　　　D. the servant

3.The rich told the servant that there was poison in the two bottles, because_______.

A. there was in face poison in the bottles

B. he did not want the servant to drink his wine

C. he wanted to kill the cat

D. he wanted to kill the servant

4.In fact, _______ate all the nice food and drank the wine.

A. the servant   B. cat   C. the rich man   D. nobody

5.From the story, we know that the servant is very _______.

A. lazy   B. bad   C. clever   D. kind