你必须懂得如何保护自己。

You have to know how to defend yourself.

youdao

痛过了，才会懂得如何保护自己；傻过了，才会懂得适当地坚持和放弃。

You'll know how to protect yourself after being hurt, understand proper persistence and give-up after becoming stupid.

youdao

现在懂得了很多，懂得如何保护自己，也知道要打电话回家问候家人，关心他们的状况。

Now know a lot, know how to protect themselves and know to call home greeting family members, concerned about their condition.

youdao