Signals running through fiber-optic cables deteriorate, and so the signals must be run through a piece of equipment called a regenerator before being transmitted farther.

通过光纤传输的信号会变弱，因此信号必须通过一种称为再生器的设备才能传输到更远的地方。

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If anyone can be called a scientific giant after Albert Einstein, that person must be Stephen Hawking.

如果有人能在爱因斯坦之后被称为科学巨人，那么这个人一定是史蒂芬·霍金。

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Rivers can differ in size and there is no strict rule on how big a flow of water must be to be called as a river.

河流的流域会有不同，对于有多大的流量才能被称为河流没有严格的规定。

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This is why he tells us parenthetically that marriage must not be called a defilement.

这就是为什么他顺便地告诉我们,婚姻不能被称为肮脏。

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But before a gene can make a protein, it must be transcribed onto a molecule called RNA. Researchers at Santa Clara, Calif.

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The opposition is determined to change all this at the next election, which must be called within a year.

ECONOMIST: Mahathir, closet westerner

To be fermented, cellulose must first be broken away from a plant stiffener called lignin.

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