A man is on a boat. He wants to tie up the boat. Something happens. He moves the throttle by accident. The boat moves. The man falls into the water.
The boat moves in a circle. Somebody sees the boat. The person calls help. Lifeboat crew come. They get a line on the boat. They stop it.
Difficult words: tie up (“park” the boat), throttle (thing which controls speed), lifeboat crew(people who help other people at sea).