广播电视英语短句 第 315 课：传染性疾病-2

She explains the problems with using human blood. 她解释了使用人血做实验存在的问题。

Doctor Yeh says tests with human blood can produce the wrong results, so they are not dependable. Yeh 医生还说到使用人血做实验会产生错误的结果，因此并不可靠。

The study found that blood from hair sheep is an excellent substitute. 该研究发现，无绒毛羊血液是很好的替代品。

It produced the same results as tests using wool sheep and horses. 因为它的实验结果和毛用羊、毛用马的实验结果是一样的。

Also, hair sheep require less care than wool sheep. 而且，无绒毛羊因为身上羊毛不多。