Plot hole: The scene where Andie comes over for dinner and moves a bunch of frilly stuff into the bathroom, happens at least one day before she comes over with the wedding album she made. In that scene, Ben goes into the bathroom to splash water on his face and discovers the pink hand towel and other stuff - that means he would not have gone into his bathroom for at least a day, or two, since she put the stuff in there, or he would have noticed it sooner.
Continuity mistake: In the scene where Andie and Ben are riding the motorcycle and she is wearing a white tank top, you can see the outline of her bra. When they go back to his parents' house and Ben takes off Andie's tank top in the bathroom, she doesn't have a bra on.
Glenda: Now Andie, I hope you know that we expect you to come back here because you have held Ben to his lowest bullshit score since his tonsillectomy and we are thrilled.
Jack: Lowest.
Andie: Why, were all his other girlfriends bullshit losers?
Glenda: What other girlfriends? You are the first girl he ever brought home! Don't you break his heart now.
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