会心的英文：
understanding; knowing

He grinned at me, as if sharing a secret joke.
他朝我龇牙一笑，好像彼此会心领略一个笑话。

Eccles turns to Harry to guffaw conspiratorially
埃克里斯转身对哈里会心地大笑起来。

If you were older you might understand.
假如你年龄再大一点，你就会理解了。

I understand that skepticism.
我明白这一怀疑论。

You have to understand how cells interact.
你必须明白细胞是怎样相互作用的。

Love is the byname of understanding and care.
爱是理解和体贴的别名。

We have reached an understanding with them.
我们和他们达成了协议。

Learn not and know not
不学无术

Know/not know what is most important and act accordingly
能[不能]按轻重缓急行事

Do you know that lady?
你认识那位夫人吗？

Do you know the Hallelujah Chorus?
你知道哈利路亚合唱曲吗？

Few know and few care.
很少有人知道，也很少有人关心。