根据文章内容，选择正确的答案。

New York，London，Paris and other big cities are exciting places to live in. There are many interesting things to see and to go to. You can go to different kinds of museums，plays and films. You can also buy things from all over the world.

But there are some problems in big cities too. It is expensive to live there and there are too many people in some places of big cities. Every year many people move to the cities to find jobs，to study at good schools.

But sometimes these people can't find work or a good place to live in. Also it is hard to keep the cities safe(安全的）and clean.

Some people enjoy living in big cities，others do not. Before moving to a big city，they should think about the problem of living there.

1.Who likes living in big cities?

2.What should people think about before moving to a city?

3.Why do many people move to the cities?

4.To live in a city is very_____.

5.From the article we can see it is hard to keep the cities_______.

How much sleep do we need? People are all different. Some people need only three or four hours of sleep a night. Others need ten hours of sleep a night. Most Americans sleep seven to eight hours a night.

Some people find it is hard to fall asleep. About one in three Americans have a problem with sleep. Many of these people can not fall asleep. The name of this problem is insomnia (失眠症). Many famous people in history had insomnia. Some of these people have special (特殊的) ideas to make themselves sleep. Benjamin Franklin had four beds. He moved from bed to bed to fall asleep. Mark Twain lay (躺) on his side across the end of his bed.

根据短文内容，判断正 (A) 误 (B)。

1.Different people need different amounts of sleep (睡眠时间).

2.Most Americans sleep more than 8 hours a night.

3.If a person has insomnia, he can never fall asleep.

4.About 1/3 of Americans have a problem with sleep.

5.Mark Twain had four beds to make himself sleep.

Cause and effect is one way to explain things that happen around us. Many things happen because something caused or influenced them to happen. Sometimes it is hard to look at a cause and find out what caused or influenced them to happen. Sometimes it is hard to look at a cause and find out what causes the effect. It may help you to start with the effect and use your reasoning(推理的) skills. Think about all the things you know that could be reasons for the effect you can see.
For example, you may see someone putting on a heavy jacket. This is the effect. To look for a cause, think to yourself, “What would take someone put on a heavy jacket?” Maybe the person is going outside into very cold weather. Maybe the person works in the penguin pen(企鹅圈养地) at Sea World. Maybe the person is going to visit an ice skating rink where the air is kept very cold. All of these things could be a cause for putting on a heavy jacket.
Now, think about a second example. The effect is a boy named Abi has to go to the head teacher’s office. What are the possible causes? Maybe he bullied(欺负) another student. Maybe he is just being picked up early. Maybe he is being given a prize!
Here is another example for you to think about its cause and effect. Cait, 13, was trying to fall asleep when her 8-year-old brother, Doug, came into her room. He looked around a bit, but seemed really out of it. Then Doug went back into the hallway and stood there looking straight up at the hall light for quite a while. Little brothers can be very strange, but this was really much too strange. Cait’s father appeared and explained that Doug was sleepwalking. What’s the cause end effect, could you tell?
根据材料内容选择最佳答案，并将其标号填入题前括号内。
【小题1】According to the second paragraph, which of the following is an effect?

根据学过的课文，判断正（T）误（F）
The Earth is a planet and it goes around the Sun．Seven other planets also go around the Sun．None of them has an environment with air，so people and things cannot grow．The Sun and its planets are called the solar system．The solar system is a small part of our galaxy．
The stars we see at night are the suns in other solar systems．There are more than 200 billion stars in our galaxy，called the Milky Way，and our Sun is only one of them．
But scientists have discovered many other galaxies in the universe．They are a long way away and their light has travelled for many years to reach us．It is hard to understand how large the universe is．
Scientists have sent lots of spacecraft to look at other planets in our solar system，and some spacecraft have gong beyond the solar system．However，no one has discovered any life in space yet．
But why has no one from other planets sent us a message？Have they tried to send information to us？With so many stars in the universe，are we alone，or is there life out there in space？We don’t know．．．yet．
【小题1】The Sun is one of the Earth planets．
【小题2】There is more than one galaxy in our solar system．
【小题3】．There are more than 200 billion stars in the Milky Way．
【小题4】．Scientists have found life on other planets．
【小题5】They’ve received no messages from space．