英语美文朗读

学习啦在线学习网 　　英语朗读通过朗读提高学生对英语的记忆,同时还加强了学生对语感的培养,提高口语水平。下面是学习啦小编带来的英语美文朗读，欢迎阅读!

　　英语美文朗读1

学习啦在线学习网 　　Cohesion-tension Theory

学习啦在线学习网 　　Atmospheric pressure can support a column of water up to 10 meters high. But plants can move water much higher; the sequoia tree can pump water to its very top more than 100 meters above the ground. Until the end of the nineteenth century, the movement of water in trees and other tall plants was a mystery. Some botanists hypothesized that the living cells of plants acted as pumps. But many experiments demonstrated that the stems of plants in which all the cells are killed can still move water to appreciable heights. Other explanations for the movement of water in plants have been based on root pressure, a push on the water from the roots at the bottom of the plant. But root pressure is not nearly great enough to push water to the tops of tall trees. Furthermore, the conifers, which are among the tallest trees, have unusually low root pressures.

学习啦在线学习网 　　If water is not pumped to the top of a tall tree, and if it is not pushed to the top of a tall tree, then we may ask: how does it get there According to the currently accepted cohesion-tension theory, water is pulled there. The pull on a rising column of water in a plant results from the evaporation of water at the top of the plant. As water is lost from the surface of the leaves, a negative pressure, or tension, is created. The evaporated water is replaced by water moving from inside the plant in unbroken columns that extend from the top of a plant to its roots. The same forces that create surface tension in any sample of water are responsible for the maintenance of these unbroken columns of water. When water is confined in tubes of very small bore, the forces of cohesion (the attraction between water molecules) are so great that the strength of a column of water compares with the strength of a steel wire of the same diameter. This cohesive strength permits columns of water to be pulled to great heights without being broken.

　　内聚压力理论

　　大气压能够支持10米高的水柱，但植物可将水送得更高。美洲红杉就能把水泵到地面以上100多米高的树顶。直到19世纪末，水在树木和其它高大植物中的输送还是一个谜。一些植物学家假定植物中的活细胞充当了水泵的角色。但许多实验表明细胞都已死亡的植物茎干仍能将水输送到相当可观的高度。对于植物中输送水的其它解释都基于根压--植物底端的根对水的推动。但根压完全不足以将水推到树顶。况且，最高树木中的松柏只有很低的根压。

　　如果水不是被泵到高树的树顶，也不是被推到树顶，那么我们会问：它是怎样到达树顶的呢?根据目前为人们所接受的内聚压力的理论，水是被拉到上面去的。一株植物中作用于一个正在升高的水柱之上的拉力来自该植物顶部水的蒸发。由于水从叶子表面丧失，一个负压力，或张力就得以产生。蒸发出去的水被植物里流动的水代替。这些水形成水柱从植物顶端一直延伸到根部。在任何水样中造成表面张力的力支持着这些不断的水柱。当水被限制在内径很小的管道中时，内聚压力(水分子之间的相互吸引力)是如此之大以致一支水柱的强度相当于一根直径相同的钢丝的强度。这种内聚压力使得水柱被拉到非常高的地方而不会断裂。

　　英语美文朗读2

学习啦在线学习网 　　Icebergs

学习啦在线学习网 　　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.

学习啦在线学习网 　　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 of in darker hues. They are graceful, stately, inspiring ----- in calm, sunlight seas.

学习啦在线学习网 　　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 their underwater parts may extend out far beyond the visible top. Also, they may roll over unexpectedly, churning the waters around them.

　　Icebergs are parts of glaciers that break off, drift into the water, float about awhile, 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.

　　As each year’s snow accumulation lay on the surface, evaporation and melting caused the snowflakes slowly to lose 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 ones. 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.

　　冰山

学习啦在线学习网 　　冰山是大自然最壮观的创造之一，但大多数人却从未看到过冰山，一种朦胧神秘的气氛笼罩着它们。冰山形成于久远的、寒冷的水体中，而且伴随着雷声轰鸣般的嘈杂和水花汹涌的风暴，但却无人耳闻目睹。冰山仅存在短短的一段时间就慢慢地悄无声息地融化掉。

　　冰山具有最纯粹的美，人们如是说。冰山呈现出千姿百态，可能白得耀眼，或者是闪耀着蓝色、绿色或紫色的玻璃般的光芒，或浓或淡。它们在平静的阳光照耀的海水中显得优雅堂皇，令人浮想联翩。

　　但是人们亦把冰山称为恐怖的和危险的。它们的确如此--在夜间，雾天和风暴肆虐时。即便是在晴朗的天气里，与它们保持一段安全距离也是明智的。冰山的大部分体积稳藏于水下，因此其水下部分的伸展远远超过可见的顶部。冰山也可能出人意料地翻滚，剧烈地搅动周围的水体。

　　冰山是冰川的一部分，从冰川断裂漂流进水中，一段时间后融化。今天的冰山由多年前降落的雪花形成。它们的体内是数百年，或数千年，有时甚至是数百万年前的降雪。这些雪花落在极地或寒冷的山上，仅有少量融化或根本不融化，这样经过许多年或许多世纪后积累了巨大的深度。

　　由于每年的雪花积累在表面之上，蒸发和融化使得雪花慢慢失去其羽状尖端而变成微小的冰粒。当新的雪花降落到旧的表面上，也变成了冰粒。因而雪花覆盖层和冰粒层层堆积起来直到如此之大的厚度以致较上层的重量压缩较下层。在时间和压力的作用下，许多小冰粒结合到一起变成更大的晶体，最终较底层的晶体合并成庞大而坚固的冰块。

　　英语美文朗读3

学习啦在线学习网 　　British Columbia

　　British Columbia is the third largest Canadian provinces, both in area and population. It is nearly 1.5 times as large as Texas, and extends 800 miles (1,280km) north from the United States border. It includes Canada’s entire west coast and the islands just off the coast.

学习啦在线学习网 　　Most of British Columbia is mountainous, with long rugged ranges running north and south. Even the coastal islands are the remains of a mountain range that existed thousands of years ago. During the last Ice Age, this range was scoured by glaciers until most of it was beneath the sea. Its peaks now show as islands scattered along the coast.

　　The southwestern coastal region has a humid mild marine climate. Sea winds that blow inland from the west are warmed by a current of warm water that flows through the Pacific Ocean. As a result, winter temperatures average above freezing and summers are mild. These warm western winds also carry moisture from the ocean.

　　Inland from the coast, the winds from the Pacific meet the mountain barriers of the coastal ranges and the Rocky Mountains. As they rise to cross the mountains, the winds are cooled, and their moisture begins to fall as rain. On some of the western slopes almost 200 inches (500cm) of rain fall each year.

　　More than half of British Columbia is heavily forested. On mountain slopes that receive plentiful rainfall, huge Douglas firs rise in towering columns. These forest giants often grow to be as much as 300 feet(90m) tall, with diameters up to 10 feet(3m). More lumber is produced from these trees than from any other kind of tree in North America. Hemlock, red cedar, and balsam fir are among the other trees found in British Columbia.

　　英属哥伦比亚

学习啦在线学习网 　　英属哥伦比亚是加拿大的第三大省，无论是面积还是人口都是如此。它几乎是德克萨斯的1.5倍，从美国边境一直向北延伸了800英里(1，280公里)。它包括了加拿大整个西海岸及附近岛屿。

学习啦在线学习网 　　大部分英属哥伦比亚多山峦。绵长而粗犷的山脉贯通南北。甚至那些沿海的岛屿都是那些存在于千万年前的山脉的遗迹。在上一个冰河时期，这些山脉被冰河冲刷侵蚀，直到大部分山脉被淹没在海中。它们的峰顶显现为沿着海岸散布的岛屿。

学习啦在线学习网 　　西南海岸地区有着潮湿温和的海洋性气候。从太平洋来的温暖的洋流使得从西吹过内陆的海风变得温暖。因此这儿冬天平均气温在零上而且夏天也不会酷热。这些温暖的西风同样也从海洋带来了湿气。

学习啦在线学习网 　　来自太平洋的、从海岸向内陆的风遇到海岸山脉和落基山脉这些山脉屏障。当气流升高跨越这些山脉时，风的温度就降低了，风中的水分形成降雨。在一些朝西山坡区域每年大约有200英寸(500厘米)的降水。

　　大部分英属哥伦比亚密布着森林。在有充足降水的斜坡，巨大的道格拉斯枞树高耸入云。这些森林巨人常常长到高达300英尺(90米)，直径粗达10英尺(3米)。这些树产出了比北美其他任何树都多的木材。铁杉、红香椿、香脂冷杉枞都是发现于英属哥伦比亚的其它树种。