Tree-planting helps to ____ water and prevent soil erosion.

Trees are useful to man 【B1】______ three very important ways: they provide him 【B2】______ wood and other produces; they help to check soil erosion and they help to 【B3】______ drought and floods.

【B4】______ , in many parts of the world, man has not realized that the 【B5】______ of these services is the most important. In his eagerness to draw quick profit from the trees, he has cut them down in large 【B6】______ , only to find that 【B7】______ them he has lost the best friend he had. Two 【B8】______ years ago a rich and powerful country cut down its trees to build warships 【B9】______ to gain itself an empire. It gained the empire, but without its trees, its soil became hard and poor. When the empire 【B10】______ to pieces, the home country found itself faced by floods and starvation. 【B11】______ a government realizes the importance of a plentiful supply of trees, it is difficult for it to persuade the villager to see this ,the villager wants wood to cook his food 【B12】______ ; and he can earn money by making charcoal or selling wood to the townsman. He is usually too lazy or too 【B13】______ to plant and look after new trees. So, 【B14】______ the government has a good system of control, or can educate the people, the forests slowly disappear. This does not only mean that the villagers' sons and grandsons have 【B15】______ trees. The results are even more serious; for where there are trees their roots break the soil up allowing the rain to sink in and also bind the soil, thus preventing 【B16】______ washed away on the surface, causing floods and carrying 【B17】______ ground away 【B18】______ it the rich top-soil, in which crops grow so well. When all the top-soil is 【B19】______ , nothing remains 【B20】______ worthless desert. A．with B．at C．in D．through

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Don’t worry．Our friendswill come to help____________．

A.ourselves B.ours C.US

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How_________I help them to understnd when they won’t listen to me cnB．wouldC．myD．Must32．How_________I help them to understnd when they won’t listen to me cn B．would C．my D．Must

A．can B．would C．may D．Must

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-Help ____ to some cakes, Jim. ---Thank you.

A．you B．your C．yourself D．yourselves

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He never hesitates to make such criticisms______are considered helpful to others.

A．that B．what C．which D．as

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To help all anxious kid out，it is suggested to_______.

A.tolerate his fears and worries B.point out his normal grow path C.put him in a particular treatment D.ask him to make a self-evaluation

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Why not__________Professor Li for help？ He is kind-hearted and willing to help.