Season 5: The measuring tape moment
Season 8: The ‘ring-and-toss-game’, Sex on the balcony
Season 9: “You are so lazy! Can’t you get on top for once?!”
Season 10: Scarf dance, “The thing we hardly ever do/the thing we never do”, “Oh sure, now they’ve locked the door, but when they’re having sex on the couch it’s like ‘hey, come on in, my butt is surprisingly hairy today!’ (LOL)
Individual ones are e.g. season 6: “The pages are stuck together!” - “Chandler!” and season 8, Monica’s sex noises while getting massaged/when she tries on the boots.
Just a few off the top of my head…