I don't even know. I think acid and base chemical reactions.

我还不知道，我想是学习酸和盐基化学反应吧。

youdao

I do not know why acid corrodes the metal.

我不知道酸为什么腐蚀金属。

youdao

How would I know what amino acid that is?

我如何才能知道这个氨基酸是甚么呢？

youdao

I didn't know about acid rain frankly, at that time.

坦白地说，那时我还不知道有酸雨。

youdao

I didn't know about acid rain frankly, at that time.

坦白地说，那时我还不知道有酸雨。

youdao