Polly: Why aren't you at school yet?
Ricky: We don't have school today.
Ben: The class went for a trip
Polly: Shit
Polly: Really? 
Polly: I must have forgotten
Ben: Were you supposed to go?
Ben: Me and Ricky, we didn't pay
Polly: I don't know. I totally forgot about this trip
Polly: I don't even remember if my mom paid
Polly: I was sick last week 
Ricky: The teacher was talking about the trip all week
Polly: Well, I missed it. 
The class went for a school trip today. Ben and Ricky hadn't paid, so they didn't go. Polly has totally forgotten about the trip and she doesn't even know whether her mother paid for it.