"In that cave," he said to himself, "there must be a fire."

“在那个洞里，”他自言自语道，“一定有火。”

youdao

Look at the fire over there! Something must be happening to Mr. Cameron's house.

看那边的大火！肯定是卡梅隆家出事了。

youdao

If there is a danger of the fuel vapours from the stored mower coming into contact with fire or sparks, all fuel must be removed from the fuel tank prior to storing the mower.

如果割草机储放时燃料挥发气体可能接触到的火源或火花，在存放之前所有的燃料必须从油箱排空。

youdao

People who want to believe in the evidence of effects appear to reason that where there is so much smoke there must be fire, but so far no one has produced the fire.

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"There's a lot of smoke, and I tell you there must be a fire somewhere, " Mr. Nordberg said during an interview.

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There had been too much smoke for too long for unbiased observers not to believe that there must be some fire, as well.

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