Trees are useful to man in three very important ways：they provide him wood and other products;they give him shade;and they help to prevent drought(干旱)and floods.

　　Unfortunately，in many parts of the world，man has not realized that the third of these services is the most important.In his eagerness to draw quick profit from the trees，he has cut them down in large numbers

　　Two thousand years ago，a rich and powerful country cut down its trees to build warships，with which to gain itself an empire It gained the empire but，without its trees，its soil became bare and poor.When the empire fell to pieces，the country found itself faced by floods and starvation.

　　Even where a government realizes the importance of a plentiful supply of trees，it is difficult sometimes to make the people realize this.They cut down the trees but are too careless to plant and look after new trees So，unless the government has a good system of control，or can educate the people，the forests slowly disappear

　　This does not only mean that there will be fewer 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.This prevents the soil from being washed away.But where there are no trees，the rainfalls on hard ground and flows away on the surface，and this causes floods and the rain carries away the rich topsoil in which crops grow When a11 the topsoil is gone.nothing remains but worthless desert.

　　41.Trees are useful to man mainly in three ways，the most important of which is that they can ____

　　A. keep him from the hot sunshine B.enable him to build warships

　　C.make him draw quick profit from them D .protect him from droughts and floods

　　42.It’s a great pity that ____

　　A.man is only interested in building empires B.man is eager to profit from trees

　　C.man hasn’t realized the importance of trees to him D. man hasn’t found out that he has lost all trees

　　43.Sooner or later the forests will disappear ______.

　　A. unless a country has a plenty supply of trees B.unless people stop cutting down their trees

　　C.unless aIl people are taught the importance of planting trees

　　D.unless the government punishes those who cut trees instead of planting them

　　44.The word“bind”in Paragraph 5 means“_____”

　　A.to wash away B.to make wet C.to make stay together D.to improve

　　45. When there is a heavy rain.trees can help to prevent floods.as they can.

　　A.keep rain from falling down to soft ground B，cause the soil to allow rainwater to sink in

　　C.prevent the soil from being washed away D .make the topsoil stick together

　　41-45 DCCCB

　　树木对于人来说有3个重要益处：树木给人类提供木材和其他产物;树木可以让人们乘凉;树木可有效地防止旱涝灾害。

　　可惜的是，在世界上许多地方，人类没有认识到以上三个作用中，第三个是最重要的。人们急切于从树木上快速的谋取利益，于是大量的砍伐森林。

　　两千年之前，有一个富裕和强大的国家。为了建立帝国，砍倒了树木来造战舰。帝国建立了，但是，没有树木的土地变得荒芜和贫瘠。当帝国四分五裂的时候，整个国家发觉自己面临的是水灾和饥荒。

　　就算在政府认识到足够的树木储备的重要性时，有时却很难让人民也意识到这点。人们砍倒了树木，却疏于种植和照料树苗。因此，除非政府建立一套体制来控制或者教育人们，否则森林就会渐渐消失。

　　森林的消失不仅仅意味着树木的减少，还有更严重的后果。在有树的地方，树根不仅把土壤粉碎成小块，便于雨水的渗入，还可以牢牢的抓住泥土，防止泥土被冲刷走。但是在没有书的地方，雨水直接落在坚硬的地面，在土地表面流走。这不仅会导致洪水，雨水还会带走庄稼赖于生长的肥沃的表层土。当所有的表层土被冲走之后，除了毫无价值的沙漠之外，什么也没有了。

　　推荐阅读：

　　2019年全国公共英语考试二级词汇练习（12套）

　　2019年公共英语二级模拟试题：完形填空汇总

　　取证热点：：2019年公共英语不用盲目备考，网校教研团队精心打造高通关套餐班，密训锁分，保障快捷通关!2019年公共英语锁分套餐班强势推出，精锐老师分题型专项辅导，听说读写稳步质变>>课程试听！

　　想获得更多试题资料？加入公共英语交流群424641146 ，还可以和考友一起交流！