Many difficulties have ________ as a result of the change over to a new type of fuel.

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We found ________ impossible to finish the work on time.

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I had to speak loud to make myself ________.

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________ he was tired, he still went on working hard.

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I advised him not to smoke, but he ________ listen to me.

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________ time is ________ forever.

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As soon as he entered the room, the boy caught sight of the presents ________ by his mother.

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Most of the artists ________ to the party were from south Africa.

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The computer centre, ________ last year, is very popular among the students in this school.

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Linda worked for the Minnesolu Manufacturing and Mining Company, ________ as 3M.

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