1. Icebergs are among nature’s most spectacular creations, and yet most people have never seen one. A vague air of mystery envel

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问题     1. Icebergs are among nature’s most spectacular creations, and yet most people have never seen one. A vague air of mystery envelops them. They come into being somewhere in faraway, frigid waters, amid thunderous noise and splashing turbulence, which in most cases no one hears or sees. They exist only a short time and then slowly waste away just as unnoticed.
    2. Objects of sheerest beauty, they have been called. Appearing in an endless variety of shapes, they may be dazzlingly white, or they may be glassy blue, green, or purple, tinted faintly or in darker hues. They are graceful, stately, inspiring — in calm sunlit seas.
    3. But they are also called frightening and dangerous, and that they are — in the night, in the fog, and in storms. Even in clear weather one is wise to stay a safe distance away from them. Most of their bulk is hidden below the water, so that the underwater parts may extend out far beyond the visible top. Also, they may roll over unexpectedly churning the waters around them.
    4. Icebergs are parts of glaciers that break off, drift into the water, float about a while, and finally melt. Icebergs afloat today are made of snowflakes that have fallen over long ages of time. They embody snows that drifted down hundreds, or many thousands or in some cases maybe a million years ago. The snows fell in polar regions and on cold mountains, where they melted only a little or not at all, and so collected to great depths over the years and centuries.
    5. As each year’s snow accumulation lay on the surface, evaporation and melting caused the snowflakes slowly to lost their feathery points and become tiny grains of ice. When new snow fell on top of the old, it too turned to icy grains. So blankets of snow and ice grains mounted layer upon layer and were of such great thickness that the weight of the upper layers compressed the lower one. With time and pressure from above, the many small ice grains joined and changed to larger crystals, and eventually the deeper crystals merged into a solid mass of ice.
    Questions 1-5
    Directions: For questions 1-5, choose the best title for each paragraph from below. For each numbered paragraph(1-5), mark one letter(A-G)on your Answer Sheet. Do not mark any letter twice.
    A. Size and shape of iceberg
    B. Snows in polar regions
    C. Beautiful appearance of iceberg
    D. The dangers of iceberg
    E. Iceberg as a spectacular creation
    F. Formation of solid mass of ice
    G Iceberg originating from the buildup of snowflakes
Paragraph 5 ______

选项

答案F

解析 第5段介绍了冰山的最终形成。蒸发和融化使雪花变成小冰粒,冰粒被积压变成晶体,晶体融合为坚固巨大的冰山。
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