One day a scuba diver was enjoying the aquatic world 20 metres deep. He noticed a guy at the same depth he was, but he had on no scuba gear whatsoever.
The diver went 20 metres deeper, but the other guy joined him a few minutes later. The diver went down another 25 metres, but minutes later, the same guy was there too.
Confused, the diver took out a waterproof chalk-and-board set, and wrote, “How are you able to stay under at this depth without equipment?”
The guy took the board and chalk, erased what the diver had written, and wrote, “I’M DROWNING, YOU FOOL!”