这是真的，在自然条件。

That's true, in natural conditions.

youdao

湖北汉江流域中下游在自然条件上与田纳西流域有许多相似之处。

There are lots of similarities between the middle and lower reaches of the Han River and Tennessee Valley in natural conditions.

youdao

在自然条件下，如果一个蜂巢产的蜜有盈余，蜜蜂会分成两个蜂群，不会浪费蜂蜜。

Under natural conditions, if the hive were producing a surplus, they would divide into

youdao

The question is, "If you're naturally exposed to antigen wouldn't this happen anyway?"

她的问题是,在自然条件下,如果接触某种抗原,那么就是否就不发生二次免疫

耶鲁公开课 - 生物医学工程探索课程节选

If there were just-- if you were trying to create a positive reaction of antigens and it showed up naturally wouldn't it create this reaction anyway in terms of your body would create antibodies like the secondary response volume to antibodies?

如果这里仅有,如果在自然条件下,尝试建立抗原的阳性反应,抗体这是否会像这样反应,以你身体为例,你的身体是否会产生,同二次免疫一样的抗体浓度

耶鲁公开课 - 生物医学工程探索课程节选

If you think about what ancient food gathering habits used to be like, you see things like this where people are out gathering food that is growing naturally, and you can think about what would-- what sort of conditions this would create and what kind of hardships it would create.

如果你想知道古代食物采集的习惯,请看这张图,人类都在野外采集自然生长的食物,你可以设想到,条件有多恶劣,生存有多艰难

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选