1 . 该是我们采取措施阻止空气污染的时候了。(keep...from)
It is high time that we took measures to_____________ .
It is high time that we took measures to
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2 . China tightened its control of the waters near the Huangyan Island ________ Chinese fishing boats ________ (阻止……做某事) being attacked in the South China Sea. (根据汉语提示完成句子)
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3 . What ________________________________ to the concert last night?
昨天晚上是什么阻止你去听音乐会的啊？
昨天晚上是什么阻止你去听音乐会的啊？
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