var-hour meter

例句：

1. 1.The car's speedometer shows it is traveling at 60 miles per hour.
   汽车的转速表显示它以每小时60英里的速度行驶。
2. 2. The tachometer on the engine indicates the correct revs for the vehicle.
   发动机上的转速表指示出适合车辆的正确转速。
3. 3.The driver used the tachometer to check the fuel level before starting the engine.
   驾驶员使用转速表在启动引擎前检查燃油水平。