她本应知道不该吃那么多。

She should have ___known ___better ___than ___to eat so much.

我本应知道不该把它告诉别人。

I should have ___known ___better ___than ___to tell it to someone.

他知道不该相信陌生人。

He ___knows ___better ___than ___to trust strangers.