1.   The main gasoline engine can be turned and its valve gear operates.

2.   And energy from the gasoline engine can recharge the battery while the car is in motion, so that no external recharging is needed.

3.   Another design has the gasoline engine run the back wheels and an electric motor turn the front wheels, giving four-wheel-drive as a bonus.

4.   As the hybrid picks up speed, the gasoline engine comes on.

5.   At higher speeds, the gasoline engine takes over, with the electric motor available for power boosts such as for passing or freeway merges.

6.   At moderate speeds, the car is powered by the gasoline engine.

7.   A gasoline engine can run on compressed natural gas, and Ford makes trucks and vans that can switch from one fuel to the other.

8.   A gasoline engine would do far worse and that may be why Hummer does not offer a gasoline model any longer.

9.   A small gasoline engine is up front.

10.   Air-conditioning can pull the battery charge down very fast, so the car automatically starts the gasoline engine to get the electric generator operating.