You would feel schadenfreude when your enemy failes

Schadenfreude - EP - was created in 1989-04.

"I was driven by schadenfreude to do it"

"I reveled in the sense of schadenfreude when I saw the armed robber run over by a dump truck as he tried to run back to his car."

This question actually answers itself because "How do you use schadenfreude in a sentence?" is a sentence.

Here are other examples of using schadenfreude in a sentence:

The evil prankster was driven by by his schadenfreude.

Schadenfreude can be felt by both the rich and poor.

It's not hard to imagine our president participating in schadenfreude during a better part of his day, especially when one considers there's so very many of us who are the victims, not to mention our children?

The German language is famous for having a special word for that: "Schadenfreude", which also exists in English as a loanword, or so I have heard.