We know that trees are useful in our everyday life. They
1 us many things, such as wood, oxygen(氧气), rubber, medicines and many other things. They can
2 tell us a lot about our climate. The following are the reasons. If you cut across a tree, you can
3 that it has many rings. Most trees grow one
4 ring every year. Because of this 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(干燥的) or very cold, the trees do not grow very much and their rings are usually
7 . When it is wet and
8 , the rings are much thicker. If the rings are suddenly very thin or suddenly very thick, this means that the
9 changed suddenly. If we look at the rings on the trees, we can
10 about the climate for a hundred years. We can see how our climate is changing today.
小题2: | A.too | B.as well | C.either | D.also |
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小题4: | A.new | B.old | C.young | D.short |
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小题5: | A.how tall | B.how old | C.how long | D.how far |
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小题6: | A.leaves | B.apples | C.rings | D.trees |
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小题7: | A.big | B.thin | C.thick(厚的) | D.long |
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小题8: | A.cold | B.cool | C.hot | D.warm |
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小题9: | A.climate | B.things | C.people | D.life |
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小题10: | A.think | B.talk | C.learn | D.change |
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