So, he intentionally inoculated his wife and two children with fluid that he got from one of his sick cows.

所以他给自己的妻子和两个孩子接种了,取自病牛的体液

耶鲁公开课 - 生物医学工程探索课程节选

And he started with a similar but different observation, and that was that cows get a disease that's very similar to smallpox.

他首先观察到一种类似但不同的情况,就是牛得了一种很像天花的病

耶鲁公开课 - 生物医学工程探索课程节选