Our planet is about years old.A．35,000B．4600C．4600 millionD．500 million 题目和参考答案——青夏教育精英家教网—

题目内容

Our planet is about ______ years old.

A．35,000

B．4600

C．4600 million

D．500 million

C解析:
略

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根据短文内容，从短文后的选项中选出适当的选项补全短文。
The earth is about 4,600 million years old. We humans have lived on the earth for only 35,000 years, but during this period we have changed our planet a lot in many ways.    1
All over the world, people have cut down millions of trees, so more and more kinds of animals and plants are disappearing. In big cities, cars and buses have polluted the air. Factories have also polluted the land and the water.
  2  It is important to the earth. But now air pollution is destroying it and that has made a very big hole in the ozone layer (臭氧层).   3 This is very dangerous because it can cause cancer.
Carbon dioxide (CO₂) in the air has increased a lot.   4 it has formed a "blanket" (毛毯) around the each.    5  This makes our earth become warmer and warmer. Therefore, this causes the level of the ocean to rise.
All these problems are very serious. We must do something to stop our earth from being polluted anymore.

A. The heat from the sun can' t escape, so the temperature is rising.
B. Too much harmful light from the sun passes through it and reaches the earth directly,
C. Some things we've done are very good for the earth while some are bad.
D. Around the earth, there’s a special kind of oxygen (O₂) called "ozone" (O₃).
E. It mainly comes from different kinds of burning materials.

When the Audet family turns on the lights at Blue Farm, they are using electricity that comes from cows—cow manure (粪肥), to be specific.

Cows produce a lot of wastes. One cow can create 30 gallons of wastes each day. Now imagine the output of over 1,000 cows at Blue Farm. That’s really a big amount.

When farmers clean their barns, they put the wastes in a big heap, and spread some of them on their fields for fertilizer(肥料). But now places like Blue Spruce Farm have a new way of using cow wastes. They use them to produce electricity.

Here’s how it works: A big machine moves back and forth cleaning the barn floor. “The cows aren’t bothered,” says Marie Audet. “They are animals of habit; they get used to it, and just lift one foot and then another to let it go by.”

The machine pushes the manure into a big 600-gallon tank like a small swimming pool. The tank is called a digester (化粪池) because what happens there is just like what happens inside a cow: Bacteria(细菌) get to work and continue to digest the manure.

Methane gas (甲烷、沼气)in the atmosphere is known as a “greenhouse” gas because it keeps heat just like a greenhouse does, causing our planet to warm up. That’s an environmental concern. But the digester has a good result. Its gas is kept and used to power electric generators (发电机).

At Blue Farm, the generators make enough electricity to power 400 homes. The Audet family sells the extra electricity they can’t use themselves.

1. We learn from the text that the Audet family is using cow wastes to ______.

A. make electricity B. produce fertilizer C. build their farm D. feed the cows

2. How are the cow wastes collected into the digester at Blue Farm?

A. Marie Audet does the work B. The job is done by machine

C. The cows lift the cow wastes D. Bacteria get to work on them

3. According to the passage, which of the following is changed into electricity?

A. The power of moving water. B. The heat of burning coal.

C. The power of sunlight. D. The heat of the methane gas

4.The new way of using cow wastes at Blue Farm might be best described as ______.

A. reducing B. saving C. recycling D. changing

5. What is the main purpose for writing the passage?

A. To introduce a new way of making electricity B. To explain how a new energy works better

C. To show a new rebuilding plan for a big farm D. To explain the reasons for green house effect

根据短文内容和首字母的提示，把所缺单词填写在短文后面的横线上。You have probably never heard of Amy Winterbourne, but she is a most

u70 woman. She lives in a house that she built herself out o 71 trash. Well, the stuff used to be called trash, but now it’s called“recycled”material. The windows and doors came from old buildings around the town that were being pulled down. The walls are made from old glass bottles that are g 72 together. The roof is made from d 73 tiles. And the fence is built out of used soda cans. Amy recently won an a74 from the Help Save Our Planet Society. The president Jackson Smith said, “Amy is an i 75 to us all.”

1. u 2. o 3. g?

4.d 5. a 6. i

任务型阅读（每小题1分，满分5分）

请认真阅读下面短文，根据短文内容回答短文后的各个问题，并将答案写在每小题下的横线上。

On Sunday, April 22, people all over the world take time out to appreciate(珍惜) the earth that we all share. It’s Earth Day, a special day to learn about our planet（星球） and how to take care of it.

On Earth Day, some people listen to speeches about the environment. Others help clean up their offices or save water and electricity at home. Your parents may even decide to take a day off from driving their cars.

The idea for Earth Day came from a U.S. Senator (参议员), who was worried about the pollution and the health of plants and animals. And the idea quickly caught on. In 1970, the first Earth Day was celebrated. More than 20 million people in cities all over the U.S. took part in. Since then, Earth Day has been used to educate people about their role in taking care of our planet.

Now, Earth Day has become a global celebration. In 1990, 200 million people from 140 countries took part in clean-ups, tree planting and other environmental events on Earth Day.

1. When is Earth Day?

_____________________________________________________________________

2. Who came up with the idea for Earth Day?

_____________________________________________________________________

3. What does the underlined sentence mean in Chinese?

_____________________________________________________________________

4. A lot of people celebrated the first Earth Day in 1970, didn’t they?

_____________________________________________________________________

5. What is Earth Day?

__________________________________________________________________

Our planet is about ______ years old.

A. 35,000 B. 4600 C. 4600 million D. 500 million

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