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When_____ in international trade, letters of credit are convenient.

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I told him to come at three _______ to bring his wife with him.

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____ one hand on the steering wheel, Ann opened a can of soda pop with her free hand.

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I often avoid _______ to parties.

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I wish that he weather_______ not so warm.

Choose the letter A, B, C or D to complete the sentences:
First of all, they are used in various aspects _________ our life such as science, industry, airline, military and so on.

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“It’s warmer in here now”. “Yes, I had Karen _______ the window.”

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Because they usually receive the same score on standardized examinations, there is often disagreement as to _________ is the better student, Bod or Helen.

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My wife wishes she______ the guitar now

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The man who was driving the truck would not admit that he had been at fault, and_______

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She’s not only beautiful_________ intelligent.

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The team_____ going back to their homes.

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It was not long before a helicopter arrived. It arrived_______

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The girl_____ behind you is naughty.

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“You’ve been redecorating your house”, “Yes, I’m thinking _______ this room white”.

Don’t disturb Amy. She _____ to sleep.

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Before I started the car, all of the passengers_____ their seat belts.

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 _____ you carry this bag for me?

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I would rather_____ poor but happy than become rich without happiness.

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He had to work hard so that he _____ his family.

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Harry is a sailor. He spends most of his life at______ sea.