他们正在检查船体外侧的舷外发动机。

They are checking the ___outboard engine on the side of the boat.

我们的渔船装了一个新的外置马达。

Our fishing boat has a new ___outboard motor.

飞机的两个外挂发动机安装在机翼外侧。

The two ___outboard engines are mounted on the outer sides of the wings.