美国工业发展最早的地区是（      ）

    Trees are useful to man in three important ways: they give him wood and other useful things, they give him cool places, and they help to stop drought and flood.

    Unluckily, in many parts of the world, man has not found that the third of these points is the most important. Man wants to make money from trees, so he has cut them down in large numbers, only to find that without them he has lost the best friends he had. And also, he is usually too careless to plant and look after new trees. So the forests slowly disappear.

    This does not only mean that man will have fewer trees. The results are even worse: for where there are trees, their roots break up soil-make the rain in-and also bind the soil, thus stopping it from being washed away easily; but where there are no trees, the rain falls on hard ground and flows away, causing floods and carrying away the rich top-soil. When all the top-soil is gone, nothing is left but useless desert.

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                                                                                                管晏列传（节选）
        管仲夷吾者，颍上人也。少时常与鲍叔牙游，鲍叔知其贤。管仲贫困，常欺鲍叔，鲍叔终善遇之，不以为言。已而鲍叔事齐公子小白，管仲事公子纠。及小白立为桓公，公子纠死，管仲囚焉。鲍叔遂进管仲。管仲既用，任政于齐，齐桓公以霸，九合诸侯，一匡天下，管仲之谋也。
        管仲曰：“吾始困时，尝与鲍叔贾，分财利多自与，鲍叔不以我为贪，知我贫也。吾尝为鲍叔谋事而更穷困，鲍叔不以我为愚，知时有利不利也。吾尝三仕三见①逐于君，鲍叔不以我为不肖，知我不遭时也。吾尝三战三走，鲍叔不以我为怯，知我有老母也。公子纠败，召忽②死③之，吾幽囚受辱，鲍叔不以我为无耻，知我不羞小节而耻功名不显于天下也。生我者父母，知我者鲍子也。”
        管仲卒，齐国遵其政，常强于诸侯。后百余年而有晏子焉。
【注释】①见：被   ②召忽：人名   ③死：为……而死

--There ______ many trees at the foot of the mountain.--But now they are slowly disappearing because of human activities.