懂事的英文：
sensible
thoughtful
intelligent

参考例句：

My little girl is very pretty and sensible.
我的小女儿漂亮懂事。

Has your daughter cut her eyeteeth?
你的女儿懂事了吗?

She used to be a naughty girl, but now she is quiet and polite.
她过去很淘气，现在又安静又懂事。

He has come to years of discretion
他已到了懂事的年龄。

His son attained to years of discretion.
他儿子已到达懂事年龄

You ought to have known better.
你本来说应该更懂事些。

He ought to know better at his time of life.
在他这样的年龄该懂事些了。

age years ] of discretion
懂事年龄,责任年龄(英国法律规定为十四岁)

I came home sadder but wiser
回到家后,我比以前伤感,但也更懂事了

"The oldest child in a family often matures quickly, learning early to take care of the younger ones."
家中最大的孩子往往懂事最快,很早就学会照顾弟弟妹妹了。

sensible是什么意思：
adj. 明智的，合理的；意识到的；明显的；有知觉的；实用的；灵敏的

Are those shoes sensible for walking?
那双鞋便于走路吗?

Did you notice the sensible difference?
你注意到明显的差别了吗？

She has an unusual sensibility for colors.
她对色彩非常敏感。

thoughtful是什么意思：
adj. 沉思的；深思熟虑的；体贴的

There was distraction in the thought.
这个念头真令人心乱如麻。

Knowledge is a servant of thought, and thought is a satellite of feeling.
知识是想法的仆人，想法又是感受的随从。

The thought of the prize was the spur for the team.
夺取锦标的思想是该队的动力。

intelligent是什么意思：
adj. 聪颖的，理解力强的；智能的

a ready intelligence
灵敏的思维

Intelligent as you are, I suspect you will fail.
尽管你聪明，我还是猜想你会失败。

They developed an intelligent solution to this problem.
针对这个问题，他们采用了非常聪明的解决方法。