The risk of crossing a single bridge is not very sudden, so I decided to die under the bridge. "oh? ) o ask for an explanation

Crossing a single bridge is not very dangerous. It is very dangerous to cross the wooden bridge. You think the wooden bridge is made of wood. If there is a horse walking on it, it is certainly dangerous.

If you slip, you will die under the bridge. It is very dangerous for a horse to walk on a wooden bridge. Once you step on the air, you will fall off the bridge and die.