The One With The Stain - S8-E7
Visible crew/equipment: When Brenda is cleaning the top of the cabinets, stage lights can be seen on the top right-hand corner of the screen. (00:11:45)
The One With The Stain - S8-E7
Plot hole: When Monica falls off the chair you can see that she is wearing a white bra because you can see some of the cup and the strap (when she says "you're not getting it". Towards the end of the episode (still the same day) we find out that Monica is meant to have the same bra on as their new cleaner, Brenda. The bra she is meant to have on is 'pink with the lacy cup'. Rachel notices that Monica is wearing that bra and she shows Monica. What happened to the white bra she had on a few scenes before? (00:11:15 - 00:19:10)
The One With The Stain - S8-E7
Continuity mistake: When Monica asks Brenda to clean the top of the cabinets so that she can get a look at her crotch, Brenda drags a chair over (with both hands) to stand on. In the next shot, she is magically holding a feather duster. (00:11:40)
The One With The Stain - S8-E7
Continuity mistake: After Gunther responds to Ross with the biting "ezels" retort, it cuts to Monica and Brenda in the living room, and when Monica falls off her chair, the rug and blue pad underneath are suddenly rolled up at the corner, then the rug is properly flat. (00:11:15)
Answer: Usually by the seventh night of Hanukkah you don't know what to get the other person, and you will probably resort to getting the other person something insignificant. Chandler is basically saying that the pen is a stupid gift.