The Marshall Plan was the engine of postwar economic growth.马歇尔计划是战后经济发展的原动力。Education is a prime mover of cultural and social change.教育是文化和社会变革的原动力。Oil is the motor of the Libyan economy.石油是利比亚经济的原动力。Oil is the dynamo of the country's economy.石油是该国经济的原动力。