Simplify the following text for a Grade 4 native English-speaking person.
Original: Roofs constructed of flat sections that are sloped are refered to as pitched roofs ( generally if the angle exceeds 10 degrees ) .
Simplified: Some roofs are sloped , or pitched , so the rain and snow fall off easily . Some roofs are flat , but even flat roofs have a little bit of pitch so the water can flow away towards a drain .