The other day, my brother drove his car down the street at ________ I thought as a dangerous speed.

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He advised that the doctor ________ .

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I wonder ________ Jenny hasn't written us recently. We should have heard from her by now.

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I wonder whether he knows ________ to write a book.

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Whether we will go there depends on ________ it will be fine or not.

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I still doubt ________ he can overcome all the difficulties.

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I asked him ________ what he was doing.

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The question is ________ can be put into practice.

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I don't know how many years ago ________ .

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People were perhaps more honest a long time ago when life was very different from ________ it is today.

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