Example of mechanical to mechanical energy?

walking, running, sound energy, flowing water

It's also called kinetic energy. It is movement, like wheels spinning.

Kinetic energy of a moving object.

Sometimes you have to think carefully as to where exactly one form of energy is transformed into another form. Take an internal combustion (gasoline or diesel) engine. The fuel is a chemical, it is...

Rotation of turbine blades, genrator, pully, wheels, lever.