Through the combination of a high-efficiency gasoline engine with an electric motor, the car's fuel efficiency is roughly 100% greater than, existing gasoline-powered cars and emissions are reduced to approximately one-tenth.
(the car's fuel efficiency; is; roughly 100% greater than) (existing gasoline-powered cars and emissions; are reduced; to approximately one-tenth)
the car's fuel efficiency existing gasoline-powered cars and emissions
is are reduced
roughly 100% greater than
to approximately one-tenth