Where does this sentence come from? Urgent! !

Li Xiaoyao: I will never forget Li Xiaoyao's great kindness to me, and I will never forget ...! ? "

Zhao Linger bowed their heads and sang:

"Don't look back, why don't you forget?

Since there is no chance, why take the oath?

Today, everything is like water without a trace;

Tomorrow night, you will be a stranger ... "

Zhao Linger said and began to cry.

-"The Legend of the Sword and the Chivalrous Man"