hand-operated direction valve

例句：

1. 1.The hand-operated direction valve is responsible for controlling the flow of oil through the engine.
   手动操作的方向阀负责控制油通过发动机的流动。
2. 2. In this case, the hand-operated direction valve was used to adjust the speed of the motor.
   在这种情况下，手动操作的方向阀被用来调整电机的速度。
3. 3.The hand-operated direction valve was a critical component in maintaining the proper functioning of the vehicle's engine.
   手动操作的方向阀是保持车辆引擎正常运行的关键部件。