英语六级阅读理解练习附详解:自然科学

　　下面是学习啦小编整理的英语六级阅读理解练习附详解:自然科学，希望对大家有帮助。

　　Icebergs are among nature's most spectacular creations,and yet most people have never seenone.A vague airof mystery envelops them.They come into being-somewhere-in faraway,frigidwaters,and thunderous noise and splashing turbulence,which in most cases no one hears orsees. They exist only a short time and then slowly waste away just as unnoticed.

　　Objects of sheerest beauty,they have been called.Appearing in an endless variety ofshapes,they may be dazzlingly white,or they may be glassy blue,green,or purple,tinted faintly ofdarker hues(颜色).They are graceful,stately(宏伟的),inspiring in calm,sunlit seas.

　　But they are also called frightening and dangerous,and that they are-in the night,in thefog,and in storms.Even in clear weather one is wise to stay a safe distance away fromthem.Most of their bulk is hidden below the water,so their underwater parts may extend outfar beyond the visible top.Also,they may roll over unexpectedly,churning(剧烈搅动)thewaters around them.

　　Icebergs are parts of glaciers that break off,drift into the water.float about awhile and finallymelt.Icebergs afloat today are made of snowflakes that have fallen over long ages of time.Theyembody snows that drifted down hundred,or many thousand,or in some cases,maybe a millionyears ago.The snows fell in polar-regions and on cold mountains,where they melted only a littleor not at all and so collected to great depthsover the years and centuries.

　　As each year's snow accumulation lay on the surface,evaporation and melting caused thesnowflakes slowly to lose their feathery points and become tiny grains of ice.When new snowfell on top of the old,it too turned into icy grains.So blankets of snow and ice grains mountedlayer upon layer and were of such great thickness that the weight of the upper layerscompressed the lower ones.With time and pressure from above,themany small ice grains joinedand changed to larger crystals,and eventually the deeper crystals merged intoa solid mass ofice.

　　冰山是大自然最壮观的杰作之一，而大多数人却从未见过。它们被一层神秘的面纱所笼罩。[1]冰山产生于某些遥远的冰冷水域中，生成时发出雷鸣般的响声，溅起巨浪，而在多数情况下没人听到或见过。它们昙花一现并渐渐消失无踪。

　　它们被誉为最美丽的物体。[2]其形状变化多端，呈现出耀眼的白色或透亮的蓝色、绿色或紫色，带着丝丝淡淡的深色。在风平浪静、洒满阳光的海面上，它们是那么优雅、宏伟、激动人心。

　　[3]然而在夜晚、在雾里以及在风雨中，它们也被认为是可怕和危险的，即使是在天气晴朗的日子，与其保持安全的距离也是明智之举。冰山的大部分体积都隐藏在水下，因此它们水下的部分远比水上可见的部分大。[3]它们还可能会出乎意料地滚动，引起周围水域的剧烈翻腾。

　　[4]冰山是断裂的冰川滑入水中的一部分，它们漂浮一段时间，最终融化。现在漂浮着的冰山是由以往漫长岁月里飘落的雪花形成。它们承载的雪是数百年乃至数千年前落下的，有的还可能是100万年前的。雪飘落在极地和寒冷的高山上，仅仅融化一点或根本就不融化，年深日久逐渐达到了很深的厚度。

　　覆盖在表面的雪年复一年地累积，蒸发和融化使雪花逐渐失去了羽状边角，变成细小的冰粒。当新雪落在旧雪上时，也变成了冰粒。就这样，雪和冰粒层层重叠，变得非常厚，以致上层的重量紧紧压住了下层。[5]随着时间的推移以及来自上层的压力，众多细小的冰粒互相结合并转变为更大的水晶，最终深层的水晶融合成巨大的坚冰。

　　1.The author states that icebergs are rarely seen as they appear in_______________of theworld.

　　2.From the passage,we can know that the shape of icebergs is___________________.

　　3.According to the passage,icebergs are scary and dangerous because they are likelyto_______________________suprisingly.

　　4.What glaciers become when they break off and drift into the water?

　　5.What are the major factors in the process of the many small ice grains being merged intoicebergs?

　　1.[faraway(distant/remote)waters(regions/areas)]