We know that trees are useful in our everyday life. They   1  us many things, such as wood, oxygen, rubber, medicines and many other things. They can  2  tell us a lot about our climate. The following are the reasons. If you   3  a tree, you can see that it has many rings. Most trees grow one new ring   4  year. Because of the reason, we know   5  a tree is. A tree over a hundred years old means that it has more than a hundred   6 . When the climate is dry or very cold, the trees do not grow very much and their rings are usually   7 . When it is wet and warm, the rings are much thicker. If the rings are suddenly very thin or suddenly very thick, this means that the   8  changed suddenly. If we look at the rings on this tree, we can learn about the   9  for a hundred years. We can see  10  our climate is changing today.

完形填空

　　One morning, Sue was riding her bike to school.She was late, so she decided to take a short cut （捷径）. But she made a mistake and 1 into a one-way street. The street was not very 2 . A car was coming from the other direction. The driver quickly drove to one side and drove into a shop window. The shop assistant was greatly 3 ! There was 4 everywhere.

　　Sue rode into the other side of the street and 5 a man, then an apple cart. The apple cart turned over and the apples went in all directions.

　　A group of students were having 6 in a small restaurant. Quickly they ran 7 the street. With their help, all the apples were 8 and put back on the cart. Luckily, 9 Sue nor the driver of the cart was hurt. A policeman came by and saw what happened. He 10 Sue from riding to school and asked her some questions, so Sue was even later for school.

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