I'm gonna do it.
Saying 'I'm gonna do it' is like a person signing their own death warrant. They're going to do something crazy, and it's usually because someone else told them to.
I'm gonna do it. I'm gonna eat that whole pizza by myself.
I'm gonna do it. I'm gonna try to ride a bike with no hands.
I'm gonna do it. I'm gonna jump off the roof just because he said I should.
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