Goofs

Rachel throws a newspaper at Ross, which hits the door. It disappears in the next shot of them arguing.

When Monica hits the blender button, she drops/throws the lid that's in her hand. Then immediately in the closeup, it's in her hand. When they go back to the wide shot, her hand is empty.

When Phoebe first waxes Joey's arm, she puts the wax on the front of it but puts the strip on the back of it. So when he pulls the strip off, there's actually no wax to hurt him.

When Rachel and Ross are arguing she is clearly wearing two rings on her left ring finger, in one take she is sitting at Monica's table and is clearly only wearing one ring, then the scene changes and she is wearing two again.

Monica, Phoebe, Joey and Chandler can hear Ross and Rachel talking in the living room, but Rachel and Ross can't hear the others talking in Monica's room, even though they're not whispering. However, Rachel and Ross are arguing loudly or even yelling at each other, and are so engrossed in their conversation they likely didn't hear anyone talking normally in the bedroom. The others have to listen at the door, meaning they can't otherwise hear them, and thus Ross and Rachel wouldn't be able to hear them either being much further away from the bedroom.

In The One Where Ross and Rachel Take a Break (1997), Phoebe and Monica had a fight over dinner with the translator and the diplomat, but in this episode they get along just fine, though it happened the night before. However, they were not seriously angry with each other over these two men. They would have quickly made up, such as they did when fighting to take care of the guy in the coma in The One with Mrs. Bing (1995).

When Ross and Rachel in the living room are arguing, the transom window above Monica's room door is open and in the shots from the interior of Monica's room the transom window is shown as closed.

The transom window over Monica's door appears open in both the scenes from the living room and the scenes from the inside of her room. In both sides the window is on inclination.

At the start Rachel stops by Ross's place before she goes to work, and she is then seen later in the coffeehouse. However, she possibly didn't go to work because she needed to talk to Ross, or more likely, she went there on her lunch break or after work, and this is when Gunther told her the news.

When Monica and Phoebe are pulling the wax strips off each others legs, you can tell that it's not really waxed on since the paper is not fully stuck to their legs. The actresses probably used water as it would hurt to actually have to wax the same leg every take. Additionally, they likely had their legs wax in real life and their legs were already smooth.