说到老鼠，人们总是想到它们偷吃食物、毁坏农作物、甚至传染疾病等种种恶习。“老鼠过街，人人喊打”这句俗语，十足地道破了人类对于鼠类的深恶痛绝之情。但是，并不是所有的鼠类全都有害，有一些鼠类极有经济价值，如松鼠的皮毛就可以做成皮革制品。如果你到大学的医学院、生 When it comes to rats, people always think of various kinds of vices such as stealing food, destroying crops, and even contagious diseases. “The rat crossed the street, everyone shouted ” This common saying, full of authenticity has broken the human disgust for the rodents. However, not all rodents are harmful. Some rodents have great economic value. For example, squirrel’s fur can be made into leather products. If you go to college medical school, students