1996 Dodge Neon Water leakage

Interior problem
1996 Dodge Neon 4 cyl Two Wheel Drive Manual

Hello, I'm Brittany and my boyfriend and I, cannot figure out why there is water leaking in the car when it rains. All the water collects on the back floor on both sides, about 2-3 inches deep.
What do you suggest?

Thanks

Britt