________ happened to be no one in the building when the fire broke out. That's to say, ________ there was no one in the building when the fire broke out.

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A．It, it happened that

B．There, it happened that

C．This, it was happened that

D．That, that happened that

I found it difficult to hear the speaker clearly because he didn't speak ________ the microphone.

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________, Sam was unable to support his family.

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He has ________ enough money ________ for his old age .

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The new building is fitted with ________ modern office equipment, which ________ by a computer company.

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Though the task ________, nobody knows whether it will be carried on to the end .

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Judged by his ________ look, he must have met with ________ problems.

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Those with book learning must develop ________ the direction of ________.

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John'd rather go fishing than ________ while Sydney prefers ________ to going skating.

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Such ________ all he has told me.

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