Sweet Taste of Liberty - S1-E3
Continuity mistake: After Lily takes off her ring in the bar, she is seen in a later shot with the ring on her left hand.

Sweet Taste of Liberty - S1-E3
Continuity mistake: When Marshall is on the phone to Barney, the green highlighter jumps back and forth from on the desk to on top of the open book.
Chosen answer: In a flash forward scene in Season 8, it shows him with his first born: a daughter.
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