Simplify the following text for a Grade 11 native English-speaking person.
Original: A watermill is a structure that uses a water wheel or turbine to drive a mechanical process such as flour , lumber or textile production , or metal shaping ( rolling , grinding or wire drawing ) .
Simplified: A watermill is an engine that uses a water wheel or turbine to drive a mechanical process such as flour or lumber production , or metal shaping ( rolling , grinding or wire drawing ) .