I can't remember 97% of what I learned in school...

But wow, can I catch when Friends uses the same reference twice...

Episode 7.24

The Director: Look Joey, there’s nothing I can do. Besides, you’re probably gonna be out by four anyway. We’ve just got one short scene. It’s just you and Richard, and God knows he’s a pro. You’ll be fine. (Walks away and sees Richard entering.) Morning Richard.
Joey: Hey! You’re here! Great! Great! Great! Let’s get going buddy, we’ve got a scene to shoot!
Richard: I’m wearing two belts.

Episode 9.21

Joey: She's so much smarter than all the girls I've ever dated. Combined! I just don't want her to think I'm stupid.
Ross: Are you wearing two belts?
Joey: Hey, what do you know!
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And yes. I love the internet for letting me track down the direct quotes, and episode numbers.