It can infect mammals and birds, but scientists know little about its effects on its victims.

它可以感染哺乳动物和禽类，但是科学家们对其影响受害者知之甚少。

youdao

So cold was it that even the animals and the birds did not know what to make of it.

实在是太冷了，连鸟兽们都不知该如何度过这寒夜了。

youdao

Birding is a great hobby and it can be enjoyable at any time of year if you are properly prepared for the season and you know where to find the birds.

观鸟是一项极好的爱好，若你在合适的季节准备，并且知道在哪里能发现鸟，观鸟将会使你在一整年的大部分时间感到愉快。

youdao

Incubate is the strange Latin word, and it's a verb -- of course, as we know-- it's a verb typically used with relation not to spirits but to gestating birds, and it literally means "to brood."

incubabat“是个罕见的拉丁词，是个动词--当然，我们知道--这个动词通常用于正在孕育后代的鸟,而不用于神灵，它的字面意思是“孵“

耶鲁公开课 - 弥尔顿课程节选

The charity said it did not know how or where the birds found in Kent came to be covered in oil.

BBC: RSPCA collects oil spill birds off Kent coast

Mr. VERRALL: Yeah, that's what I normally do for, like, (unintelligible) and for birds, is like just make sure to grow extra, because you know, it's their place too.

NPR: Vegetable Gardening On A Budget

It underscores that even after 150 years of scientific study we still do not know all the birds in the Indo-Malayan region.

NPR: Brown-And-White Whistling Owl ID'd As New Species