I'm very sorry. I've ________ the book you ________ me last week at home again.

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The visiting professor ________ giving lectures to students ________ invited to meetings at times.

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David works hard at maths.

　 ________, and ________.

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My job today is ________ all the flowers in the garden.

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At the shopping-centre, he didn't know what ________ and ________ with an empty bag.

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I wonder why Jenny ________ us recently. We should have heard from her by now.

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Tom told me that he ________ on July 2,1982.

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She told me that she ________ you in London a year before.

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Mary said that she had to finish the experiment ________ week.

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I don't doubt ________ he will pass the exam.

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