When a sis spills the cold tea

We know that already.

Spew-it-knew-it theory says that students commonly retain a lot of information for an important test/exam but then mostly forget about it once they don't need to know it anymore.

Believe it or not this has actually been backed up by real research by Hermann Ebbinghaus.

What you say so you won't look stupid in front of your crush, when you really did not know that.

A song about realizing that something or someone isn't going to work out or it will never be. The Moment I Knew is written and sang by Taylor Swift.
a.k.a. this song is my life

A way to describe something someone said that you already knew

A way not to react when people come out to you, according to Dan