有些汽车还有超速传动齿轮，可使汽车长途行驶时节省用油。

Some cars have an extra gear called overdrive which allows them to travel long distances using less gasoline.

youdao

有些汽车还有超速传动齿轮，可使汽车长途行驶时节省用油。

Some cars have an extra gear called overdrive which allows them to travel long distances using less gasoline.

youdao