When the leash goes slack.
A dog knows what is 'no'.
Trying to win a new mattress in a contest and I need a clean mattress joke to win (dumb, I know)
Just one. But he will pull it back out and stick it back in again just to make sure hes got the right hole.
The dentist pulls it out when it hurts.
A parachute.
Parachute
The leash goes slack
Pulled Pork
The leash goes slack.