How a river is Formed.
A river starts from a source, a source is on a mountain so when the snow melts it goes down hill because of gravity.
Oceans and sea
The sea water is not good to drink because it is very salty and not good for you. The ocean covers 70% of the world .There is an oceans called the Indian Ocean.
When the river meets the sea it is called the mouth.The river water can be drank but you need to filter it first. If you see a river it and it is curvy it is called meander.