A group of boys from China stood at a manhole. One of them threw a lit firecracker into the manhole. That manhole, as well as the manhole next to it, exploded.
The explosion hit the group of boys, but it injured nobody. However, one boy fell into the hole and he almost dropped down. The other children, people who were around, and a police officer managed to save him.
Difficult words: manhole (a covered hole in the surface of a road), lit (burning), firecracker (a loud explosive firework).