Do you know what time ________?

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It's six o'clock now, it's time ________.

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Tell Lin Tao to ring me up if he ________ back.

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--What shall we do this Sunday?

--Why ________ to the Science Museum?

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The school trip________ be pleasant, if it were sunny today.

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In the street I met the scientist ________ gave us a talk last week.

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We'll climb Xiangshan Hill if it ________ tomorrow.

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We can't come into the teachers' office ________ permission.

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Lucy writes as ________ as Lily. They are both good students.

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I don't know ________ to play this new game.

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