根据句意和汉语提示，填写单词或短语

1. Here are some useful 　　  　   (网站) for you to collect information.

2. Who is helping the teacher 　　  　   (分发) the students’ exercise books?

3. The two girls are twins, and they look very 　　  　   (相似的).

4. Dad got his watch 　　  　   (修理) yesterday afternoon.

5. Jim has 　　  　   (张贴) many “No Parking” signs outside his gate.

The bicycle is really and important means of transportation in China.Bicyclese have become more and more popular in China.People ride bikes to their workplaces,to shopping centers,to schools,and so on.During the rush hour,you can often see a boiling sea of bicycles running in all directions.With the largest number of bike riders in the world,China is often referred to as the kingdom of bicycles.There are many advantages(优点) about the bicycle.For example,bicycles do not cause air or sound pollution(污染);compared with cars,bicycle cause no environmental(环境的) problems;bicycles save energy(能源) and parking place;riding bikes to travel can be a wonderful experience(经历);the bicycle allows us to go anywhere nearby easily;bikes are not very expensive,and almost every family can afford them;riding bikes regularly does good to people's health.

　　通读短文，然后根据短文内容回答问题。

1.Why is China called the kingdom of bicycles?

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2.Can we go anywhere easily by bicycles?

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3.Why can almost every family afford bicycles?

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4.What do you think the most popular means of transportation in China is?

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5.What are the advantages of the bicycles?You can give one or two examples.

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The Bermuda Triangle(百慕大三角)is in the Atlantic Ocean, near Florida in the USA. During the past 60 years, more than 1,000 seamen in ships and pilots in planes have lost their lives. It is known as “The Triangle of Death”for its strange seawater and sudden storms. What's the strangest is the light of the seawater, which looks so bright that it can be seen even from an outer spaceship.

　　At 2:00p.m. on Dec. 5, 1945, five planes took off in fine weather from the airport of Florida, on a training task. Two hours later, the leader in the sky radioed that he was “completely lost”. Then there was silence. Another plane was sent to look for them and also disappeared.

　　One of the largest ship that had disappeared in the triangle was an American coal ship, 500meters long. The weather was good, and there were no messages for help before it was “gone”. No broken ships or dead bodies have been found so far.

　　No one is able to tell how all these accidents have happened. A group of Japanese scientists were there to see what it was really like in 1995, but nothing has been heard of them ever since.

1. What is the passage mainly about?

　　A. How the Bermuda Triangle ate up the planes and ships.           

　　B. Why many of the planes and ships have disappeared.

　　C. Strange accidents happened in the Bermuda Triangle, no one can tell why     

　　D. When the Bermuda Triangle was formed very strangely.

2. How many planes had lost in December 1945?

　　A. Five. 　　　　B. Six. 　　　　C. Seven.　　　　 D. Eight.

3. What does the underline word “radioed” mean?

　　A. Wrote sound message using a radio.

　　B. Listened to sound message using a radio.

　　C. Sent sound message using a radio.

　　D. Received sound message using a radio.

4. Why was the leader in the plane lost?

　　A. He met with terrible weather.                       

　　B. He was losing the right direction.

　　C. Airport didn't give him an answer.                  

　　D. The reasons are still unknown.

5. What about the group of Japanese scientists who went to Bermuda?

　　A. They have also disappeared very strangely.

　　B. They have not heard of anything important.

　　C. They are still working hard in Bermuda.

　　D. They've come back, knowing nothing about it.

Every object has weight. But the center of its weight is not always in the middle of the object. If the top of an object is heavier than its bottom, it will fall over easily. We say that its center of gravity is high. But if the bottom is heavier, it won’t fall easily. Then we say that its center of gravity is low.
Look at the first picture. This empty box must fall over, because its center of gravity (C) is not above the line of its bottom (AB).
Now look at the second picture. There is some heavy iron in the bottom of this box. It will not fall, because its center of gravity is above its bottom.

【小题1】If the bottom of an object is ______ its top, it will fall over easily.