The context of the following conversation is Jesse rode a roller coaster at the fair. They should know they are in danger.:
Jesse says That roller coaster at the fair was so scary..
The friend responds It looked really dangerous, you rode it?.
Jesse responds Yeah, it was shaking the whole time..
The friend responds I would never ride a fair roller coaster, they're built in a day..
Jesse responds I didn't know that..
The friend responds Now you know they're dangerous..