试题题干
Translate the following sentence into Chinese.
To pollute means to contaminate—to spoil something by introducing impurities, which make it unfit or unclean to use.
参考答案
试题解析
考点：pollute污染；contaminate玷污 ；impurity杂质。
句子结构：主句为To pollute means to contaminate，破折号后为解释说明，which引导定语从句修饰impurities。