She is unschooled in the way of the world.

她不懂人情世故；她丝毫不懂世态炎凉。

Ignorance of the law is no excuse.

不懂法律不能口。

I have no conception of what he means.

我完全不懂他的意思。

Do not coin terms that are intelligible to nobody.

不要生造谁也不懂的词语。

People often derogate what they don't understand.

人们常诋毁他们不懂的东西。

These rookie cops don’t know anything yet.

这些新警什么都还不懂。

I do not understand the purport of your remarks.

我不懂你那番话的要义。

I haven't the faintest what it means.

我完全不懂这是什么意思。

Mechanics is out of my territory.

我不懂力学。

We drove past a signpost I couldn’t read.

我们驶过一路, 可是我读不懂。

He felt people were contemptuous of his lack of sophistication.

他觉得人们看不起他不懂人情世故。

I really can't understand his amorphous ideas.

我真的弄不懂他那些乱七八糟的想法。

He is a stranger to Latin.

他不懂拉丁文。

When they start talking about economics, I’m out of my depth.

他们开始讨论经济问题，我就茫然不懂了。

I haven't the faintest notion what you're talking about.

我对于你所讲的话一点儿也不懂。

I could not grasp her meaning.

我不懂她的意思。

He spoke such a jargon I couldn't make head or tail of what he said.

他讲那么一种方言土语, 我根本不懂他说什么。

I don't understand you.

我不懂你的话。

I'm a stranger to Spanish.

我不懂西班牙文。

The boys should not be trained to be an impractical person who can't even boil an egg.

"孩子们不应该训练一个不懂实际,甚至连煮个鸡蛋都不会的人。"