A：I hear scientists in the US have discovered a new AIDS vaccine.

我听说美国的科学家发明了新的艾滋病疫苗。

B：Does it work?

它有效吗?

A：I don’t know. The report says it is better than the old vaccines.

我不知道。报告说它比旧的疫苗有用。

B：Don’t count on it. I think the best way to prevent AIDS is to keep yourself clean by having clean sex and keeping a regular sex partner.

不要依赖疫苗。我觉得预防艾滋病的最好方式是通过拥有干净的性关系和固定的性伴侣保持自身的干净。

A：Right. That’s why doctor say AIDS prevention means cleanness.

说得对。那就是为什么医生说艾滋病的预防在于洁净。