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Why the dinosaurs died out $is\, not\, known.$

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With a thundering roar the huge rocket $soared\, up$ from the launching pad.

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We look forward to $hear$ from you.

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While crossing the highway,a five-year-old child was knocked $out$ by a passing car.

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If you are not clear about the meaning of a word,it is wise to $look\, to$ a dictionary.

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When it was feared that the serfs might go too far and gain their freedom from serfdom,the protestant leaders joined the princes $at\, crushing$ them.