Look around when _____ the street.

　　A. across　B. crossing   C. crossed　D. to be crossing

Look around when ___________ the street.

　 A. across　　　　 B. crossing　　　　 C. crossed　　　 D. to be crossing

Look around when ________ the street.

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Look around when ________the street.

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从所给的四个选项中选择最佳答案

Look around when ________ the street．　　　

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A．across　　　B．crossing　　　C．crossed　　　D．to be crossing