Once your business is international,________ constantly will be part of your life.

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The picture ________ on the wall is painted by my nephew.

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Teachers ask their students to ________ their work.

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A．be careful with

B．be careful of

C．be careful to

D．be careless with

—Excuse me, is this Mr. Brown's office?

—I'm sorry, but Mr. Brown ________ works here. He left about three weeks ago.

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—What do you think made Mary so upset?

—________ her new bicycle.

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A．As she lost

B．Lost

C．Losing

D．Because of losing

I was about ________ the door ________ the telephone rang.

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Hasn't the money you lent me ________?

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He made another trip to America, ________ is of importance to China.

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Can I join your basketball team?

You can when you ________ a bit older.

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Do you remember one afternoon ten years ago ________ I went to your house and borrowed a diamond necklace.

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