unpowered rudder

例句：

1. 1. The unpoweredrudder was difficult tocontrol.
   这个无动力舵很难控制。
2. 2.The pilot had to rely on the windfor direction instead of the unpowered rudder.
   飞行员不得不依赖风向而不是无动力舵来导航。
3. 3. Theunpowered ruddermade it difficult to turn theship.
   这个无动力舵使得船只难以转向。