“The maths problem continued to puzzle the teacher” means “The maths problem was still a puzzle ________ the teacher.”

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I ________ while reading the English textbook, luckily, my roommate woke me up in time!

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There were ________ flies everywhere in my house.

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I examined it carefully ________ some language experts.

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As many people know, Russians were the first to send a man ________.

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No girl who ________ herself would go out dressed like that.

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His father, ________ likes painting, is a teacher.

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The use people make ________ the coal is efficient.

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I hated the way ________ he treated me.

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Sunday is the day ________ people have a rest.

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