点击下方单词,选择对的这个单词
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1. 试剂，试药（常用以测试某一成分存在与否）A reagent is a substance that is used to cause a chemical reaction. Reagents are often used in order to indicate the presence of another substance.
1. a chemical agent for use in chemical reactions
多通过句子记忆单词，而不是单独死记硬背。
