Mr. White ________ at 8∶30 for the meeting, but he didn't show up.

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He paid for a seat, when he ________ have entered free.

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I ________ have been more than six years old, when the accident happened.

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He ________ have completed his work; otherwise, he wouldn't be enjoying himself by the seaside.

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Allen had to call a taxi because the box was ________ to carry all the way home.

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________ to sunlight too much time will do harm to one's skin.

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________ the meeting himself gave them a great deal of encouragement.

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It's impossible ________ back the wheel of history.

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It's good ________ morning exercises.

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There is no ________ here.

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