题目内容
6. This new kind of chemicals will help keep the air,soil and water from pollution.
6. free考査形容词。
free from免于，没有。句意：这种新的化学物质会有助于保持空气、泥土和水免于污染。
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6. This new kind of chemicals will help keep the air,soil and water from pollution.
6. free考査形容词。
free from免于，没有。句意：这种新的化学物质会有助于保持空气、泥土和水免于污染。