[by:聽(tīng)力課堂網(wǎng)|http://m.42bites.com|
Lesson 47
第47課
Television Day:The sea
電視日:海洋
If you looked at the Pacific from a space-capsule
如果你從宇宙飛船船艙觀察太平洋,
you might think that the world was all water.
你也許會(huì)認(rèn)為地球是一片海洋.
You would hardly be able to see any land at all.
你幾乎看不到一點(diǎn)陸地.
Water covers most of the earth's surface.
地球表面的大部分是由水覆蓋著的.
The sea contains a large number of substances,besides common salt.
海洋還含有大量的其他物質(zhì),除了鹽以外.
If you boiled away some sea-water,
如果你把一些海水煮干,
you would find over forty different materials.
你就能發(fā)現(xiàn)有40多種物質(zhì).
For instance,out of a cubic mile of water
舉例說(shuō),從一立方英里的水中
you would get ninety-four tons of silver and three tons of gold.
就能提取94噸銀子和3噸金子.
If it were possible to do this,
即使有可能這么做的話,
it still wouldn't be worth the trouble.
也不值得.
It would cost more to obtain these precious metals than they are worth.
要獲取這些有價(jià)值的金屬的成本要高于它們自身的價(jià)值.
But the sea provides us with a great many materials which we can obtain easily
不過(guò),海洋為我們提供了大量的物質(zhì)
and which we use a lot.
我們易于獲取并使用廣泛的.
For instance,we use huge quantities of sand in industry to make glass,
例如,在工業(yè)上我們使用大量的沙子制作玻璃、
detergents and cement.
洗滌劑和水泥.
Besides materials like salt and sand,
除了諸如鹽和沙子這類物質(zhì)外,
we obtain a great deal of food from the sea.
我們還從海洋中獲取大量食物.
One day we may even have undersea farms.
有朝一日我們還能有海底農(nóng)場(chǎng)呢?
We have hardly begun to explore the sea.
我們尚沒(méi)有開(kāi)始探索海洋
In some ways it is less familiar than outer space.
從某些方面說(shuō),海洋比宇宙空間還要陌生.