Of the two sisters, Betty is ______ one, and she is also the one who loves to be quiet.

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I wish you'd do ______ talking and some more work. Thus things will become better.

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The old man, ______ abroad for twenty years, is on the way back to his motherland.

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--I'll tell Mary about her new job tomorrow.

--You ______ her last week.

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A．ought to tell

B．would have told

C．must tell

D．should have told

It is known to us that it takes years of ______ practice to gain ______ skills of ______ expert.

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Mr. Bush is on time for everything. How ______ it be that he was late for the opening ceremony?

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A left-luggage office is a place where bags _______ be left for a short time, especially at a railway station.

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She is two hours late. What ______ to her?

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A．may happen

B．is happening

C．can have happened

D．must have happened

If your boss is not right, you ______ him.

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A．mustn't obey

B．don't have to obey

C．wouldn't have obeyed

D．can't have obeyed

You ______ take your umbrella. The radio says it will be clear today.

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