tractor chassis

例句：

1. 1. The tractor was used to pull the heavy loadacross the field.
   这台拖拉机被用来拖动沉重的货物穿过田野。
2. 2. The tractor chassis is made of steeland has a powerful engine.
   拖拉机底盘由钢制成，发动机强劲。
3. 3. Thetractor chassisis designed to be lightweight andeasy to maneuver.
   拖拉机底盘设计轻便且易于操控。