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(劇烈攪動(dòng))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.

　　冰山是大自然最壯觀的杰作之一，而大多數(shù)人卻從未見(jiàn)過(guò)。它們被一層神秘的面紗所籠罩。[1]冰山產(chǎn)生于某些遙遠(yuǎn)的冰冷水域中，生成時(shí)發(fā)出雷鳴般的響聲，濺起巨浪，而在多數(shù)情況下沒(méi)人聽(tīng)到或見(jiàn)過(guò)。它們曇花一現(xiàn)并漸漸消失無(wú)蹤。

　　它們被譽(yù)為最美麗的物體。[2]其形狀變化多端，呈現(xiàn)出耀眼的白色或透亮的藍(lán)色、綠色或紫色，帶著絲絲淡淡的深色。在風(fēng)平浪靜、灑滿陽(yáng)光的海面上，它們是那么優(yōu)雅、宏偉、激動(dòng)人心。

　　[3]然而在夜晚、在霧里以及在風(fēng)雨中，它們也被認(rèn)為是可怕和危險(xiǎn)的，即使是在天氣晴朗的日子，與其保持安全的距離也是明智之舉。冰山的大部分體積都隱藏在水下，因此它們水下的部分遠(yuǎn)比水上可見(jiàn)的部分大。[3]它們還可能會(huì)出乎意料地滾動(dòng)，引起周圍水域的劇烈翻騰。

　　[4]冰山是斷裂的冰川滑入水中的一部分，它們漂浮一段時(shí)間，最終融化。現(xiàn)在漂浮著的冰山是由以往漫長(zhǎng)歲月里飄落的雪花形成。它們承載的雪是數(shù)百年乃至數(shù)千年前落下的，有的還可能是100萬(wàn)年前的。雪飄落在極地和寒冷的高山上，僅僅融化一點(diǎn)或根本就不融化，年深日久逐漸達(dá)到了很深的厚度。

　　覆蓋在表面的雪年復(fù)一年地累積，蒸發(fā)和融化使雪花逐漸失去了羽狀邊角，變成細(xì)小的冰粒。當(dāng)新雪落在舊雪上時(shí)，也變成了冰粒。就這樣，雪和冰粒層層重疊，變得非常厚，以致上層的重量緊緊壓住了下層。[5]隨著時(shí)間的推移以及來(lái)自上層的壓力，眾多細(xì)小的冰粒互相結(jié)合并轉(zhuǎn)變?yōu)楦蟮乃В罱K深層的水晶融合成巨大的堅(jiān)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)]