Answer:
Well if you think about it, the three main forces that cause erosion are ice wind, and water. Water is obviously the main cause of erosion on earth rivers and rivers can create a significant amount of erosion over time. They can break up particles along the river bottom and carry them downstream.
Curved Rivers can be caused when an animal or a disturbance digs in the dirt near the river and the hole dig by the animal is used for their home and protection. The dirt that they dug is called a hollow, the river water with take small particles from the hollow and the river water will rush a little faster and faster until the place the animal dug is filled with water. This is an on going cycle that happens all the time with nature and time itself.