聽(tīng)力每日練習(xí) listen 4584 What on earth is it

 
2--Nanometer is a length scale. It's one billionth of a meter, roughly ten times the size of an individual atom.
 
1--Hmm...it's hard to figure out the exact size,l'm afraid.
 
2--Well,let's make it this way.For comparison ,10 NM is 1000 times smaller than the diameter of a human hair. There are as many nanometers in an inch as there are inches in 400 miles.
 
1--I see.Thank you.
 
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注解：
 
1.on earth到底
2.roughly大致
3.comparison比較
 
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譯文：
 
1--麥克，現(xiàn)在好多人都在談?wù)摷{米。它到底是個(gè)啥呀？
2--納米是個(gè)長(zhǎng)度單位。一納米等于十億分之一米，大概比一個(gè)原子小10倍吧。
1--嗯…恐怕還不太容易想像得出它的具體大小呢。
2--這樣說(shuō)吧。10納米比一根頭發(fā)直徑的1/1000還短。一英寸所含的納米數(shù)量等于400米所含的英寸數(shù)。
1--這樣說(shuō)我就明白了。謝謝啊。