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

One of the best and easiest pets to take care of is a mouse. It is easier and cheaper than a dog, and it is a better friend than a cat. A mouse is interesting to watch. It loves being with people. And it does not bite and scratch some other pets.

A mouse's house is not as expensive as a dog's. You can use a shoe box, but a stronger box is better. It will be easier to clean. Put a smaller box into the bigger box, too. That is important. Sometimes dogs and cats will try to eat your mouse. They are very dangerous! Your mouse can run into its little box. It will be safer and happier there than in the big box.

A mouse needs a lot of exercise. It does not like having nothing to do. So give it something to climb on. Make two floors in its house. Then it can climb up and down.

A mouse eats everything. It loves fruit. It does not eat as much as some pets, but it eats more often. Give it something to eat two or three times every day. Like all animals, a mouse needs good, clean water. A bottle is better than a bowl, but a bowl is better than nothing. Do not forget to wash its food and water bowls every day.

1. For the text, find a suitable summary(总结).(　)

A. A mouse is a better friend than a cat.

B. The advantages(优点，长处) of keeping a mouse as a pet.

C. A mouse is easier and cheaper than a dog.

D. A mouse eats everything. It loves fruit.

2. Why is a pet mouse better than a dog?(　)

A. It does not eat as much as dogs.

B. It needs a lot of exercise.

C. It is easier and cheaper than a dog.

D. It needs good, clean water.

3. What does a pet mouse need a lot?(　)

A. Exercise.　　　　　　　　　　    B. Water.

C. Fruit.　　　　　　　　　　    D. Food.

4. What should you do every day to take care of your mouse?(　)

A. Give it something to eat two or three times every day.

B. Give it gooD. clean water.

C. Wash its food and water bowls every day.

D. A, Band C.

5. Why put a smaller box into the bigger box for a pet mouse?(　)

A. It is stronger there than in the big box.

B. It is cleaner there than in the big box.

C. It is warmer there than in the big box.

D. It is safer and happier there than in the big box.

     Growing mushrooms (蘑菇) is probably the easiest thing you can do even if you are new to mushroom growing. It is becoming more common because restaurants are starting to create more dishes that include mushroom .

     Mushroom growing is easy. To start, you need to have a space where you are going to grow these mushrooms. It does not have to be a huge place but just enough for you to grow as many mushrooms as you need. When you have found the space perfect for you,you can start researching what kind of mushrooms you want to grow. There are a lot to choose from and not all of them are suitab1e to eat.

When you decide what kind of mushrooms you want to grow, you can start getting ready to plant the mushrooms. Sometimes you may want to need some workers to help if you have a large mushroom farm, or if you are trying to start a large mushroom growing business. Trying to have a business by yourself can he hard. If you don't have enough time to spend taking care of everything yourself, some helpers may be the best choice.

 After you have started the mushroom growing, you should regularly check that your mushrooms grow proper1y and that they are not being attacked by any pesticides (农药) or any other animals or something that could be dangerous to them. That is the worst part of mushroom developing.Protect your mushroom farm well with a fence (篱笆) or a gate so that only you and your workers can get in and out.

 Mushroom growing is not difficult and it is easy to get started in the world of farming.

66. According to the passage , many people begin to plant mushrooms probably because__________ .

A. they are in great need                B. they look very beautiful

C. they are healthy food                D. they are very expensive

67. The right order(顺序) of planting mushrooms is _________

   a. Choose suitable mushrooms.

   b. Protect your mushrooms well.

   c. Find some workers to help you.

   d. Find a place to plant your mushrooms.

   A. c --a --b-- d     B. d--a--c --b     C. c--a--d --h     D. d--a--b--c

68. In order to protect your mushroom farm well, you need ________________ .

    A. some workers                 B. a perfect place

    C. a fence or a gate               D. good mushrooms

69. From the passage, we can learn that ______________ .

    A. anyone can produce high quality mushrooms

    B. having a mushroom business by yourself is easy

    C. you needn't take care of your mushrooms after they are planted

    D. some helpers may be necessary if you have a large mushroom farm

70. The best title of the passage is" ___________".

    A. Healthy mushrooms

    B. The value of mushrooms

    C. Suggestions on growing mushrooms

    D. Suggestions on choosing mushrooms