Two polish guys decide to rent a boat and go fishing. They pay the rental fee and drive off in one of the boats. They are boating around trying to catch fish but are having no luck. Finally, they find this little spot where the fish are biting. They catch alot of fish and decide they have to head back before it gets too dark. The one guy says to the other;

"We should come back here tomorrow and catch more fish", "sure" says the other "but how will we find the place again?"

"I know, we'll draw an x on the bottom of the boat to mark the spot!" he says. "Are you stupid?" says the other "How do you know we'll get the same boat next time?"