Four elementary-aged children , two boys and two girls , play on a green lawn with a tree and a building in the background .
Chances are about even that 4 kids are playing tag and throwing water balloons at each other .
Chances are about even that 4 kids are playing tag and throwing water balloons at each other .
It is almost certain that 4 kids are playing tag and throwing water balloons at each other .
4 kids are playing tag and throwing water balloons at each other .