Do not play in the Car Park

This sign, which I found at a car park in my neighbourhood, consists of two Japanese sentences. The sign seems to be particularly aimed at children, because the words take the simplest and easiest form of Japanese (the form is called hiragana), which even small children are able to understand.

It's the second sentence, which starts from the second line on the sign, that is asking not to play in the car park. What the first sentence communicates is a bit difficult to be put into English, but something like "That will be annoyance."