It is believed by some that experience of the past few centuries shows that major events in the first two decades usually determine or influence the direction of world history for a century.

有人说，过去的几个世纪里，往往头二十年的大事决定和影响着整个世界的历史走向。

youdao

Fish are usually nearsighted, although it is believed that sharks are farsighted.

鱼通常是近视眼，虽然人们认为鲨鱼是有远视的。

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Ten per cent believed that if the option had been legally available, they would already have requested euthanasia, usually because of uncontrolled pain.

的人认为如果安乐死能够合法得到，他们早已经要求进行安乐死了。

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Ouchi is believed to have absorbed about twice the amount of radiation that is usually considered fatal, though he may survive.

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Growth of phytoplankton in certain areas is usually limited by lack of iron in the water, and the sub polar Atlantic is believed to be one of these areas.

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