How Earth Is Cracked Like a Giant Eggshell

1.permanent a.永久的,不变的,固定的

例句:The incident left permanent traces on his mind.
      那件事在他头脑里留下了永久的印象。

2.crust n.外壳,坚硬的外壳,面包皮

例句:Belts of mountains are cause by movements in the earths crust.
      山丘带是由地壳移动而形成的。

3.tectonic a.筑造的,建筑的,构造的

例句:circum-Pacific tectonic belt
      环太平洋构造带

4.burst n.突然破裂,爆发

例句:The athlete has an electrifying burst of speed.
      这个运动员具有惊人的爆发速度。

5.mixture n.混合;混合物,混合剂

例句:This mixture will resolve into 2 simple substances.
      这混合物会分解成两种简单的物质。

6.intense a.非常的,强烈的,紧张的,热情的

例句:We needed to rest from the intense heat of the desert.
      我们得休息一下,避开沙漠的酷热。

1.Scientists explain that the surface of our planet is always in motion.

in motion在开动中, 在运转中

例句:Friction is a form of resistance for an object in motion.
      摩擦力是一种阻止物体相对运动的阻力。

2.Only since the nineteen-sixties have scientists begun to understand that the Earth is a great, living structure.

Only倒装

    在句首的only如果后面跟了副词、介词短语或从句等状语,则主句用倒装结构。如only后跟
    的是主语,就不用倒装结构了。例如:
    only when the war was over in 1918 was he able to get back to work.
    only in this way can you learn english well.
    only after a bitter struggle was the aim achieved.
    only the teachers are allowed to use the room.(不倒装)
    only five men were hurt in the accident.(不倒装)

    注意,only和所修饰的状语如果不在句首,则不倒装。

    如:

    the boy was helped out only when his father arrived in a hurry.
    only then did he realize the importance of english
    只有在那时候他才意识到英语的重要性。
    only then ,是过一小会儿的意思,一般用在句首,引导倒装句。
    例句only then did he realize the importance of english.
    解析:在句首的only如果后面跟了副词、介词短语或从句等状语,则主句用倒装结构。如only后跟的是主语,就不用倒装结构了。
    再比如
    only when the war was over in 1918 was he able to get back to work.(倒装句)
    only five men were hurt in the accident.(不倒装)