狗是通过味道来分辨同类的，对人也一样，狗的味觉是人类的几十倍，通过嗅觉来确定犬类公母，发情情况，母仔识别等等等等，说狗是看鼻子存活并不是很夸张的说法。 剑桥雅思10test2听力答案及解析汇总下载地址：http://www.acadsocc

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