There's the monster, of course. It's the main source of conflict in the story. It could be a big, hairy, and scary - looking creature with sharp teeth and claws. And then there are often villagers or townspeople who might be aware of the monster and warn the travelers about it.
I don't know the specific 'under the bridge the true story', so I can't tell who the main characters are.
The main characters are usually the troll and the traveler who wants to cross the bridge.
Typically, there is the troll, which is the main antagonist. It lives under the bridge and tries to stop people from crossing. And then there are the travelers or the heroes who want to cross the bridge. They could be villagers, knights, or just ordinary people on a journey.
I'm not sure as the title doesn't give much away. It could be anyone from homeless people to passers - by who had an important role in the events under the bridge.
I don't know as I haven't read it. It could be a group of misfits who gather under the bridge, like a young runaway, an old storyteller, and a street artist.
Typically, there are the kids or travelers who want to cross the bridge. They are the ones who face the challenge of the troll. And of course, the troll is a main character. It is the one that guards the bridge and creates the conflict in the story.
One possible moral could be that we should face our fears instead of avoiding them. In the story, the characters often have to deal with the monster under the bridge, which represents a fear. By confronting it, they might grow or learn something valuable.
There could be a group of characters. For example, an older character who has a lot of life experience and serves as a guide for a younger character. The younger character might be struggling with something from the past, and the older one helps them see that it's like water under the bridge and they should focus on the present and future. There could also be some side characters that add to the overall story and the development of the main characters.
Since I don't know the specific 'under the bridge story', it could be anyone. It might be a local vagrant who spends most of his time under the bridge.
Since I don't know the exact 'under the bridge original story', I can't say for sure what the main characters are. It could be a lonely traveler who takes shelter under the bridge, or it could be a group of children exploring the area under the bridge.