lever of the first kind

例句：

1. 1. The car's steering wheel is a simple lever that controls the vehicle's direction.
   汽车的方向盘是一个简单的杠杆，控制车辆的方向。
2. 2. The scientist used a lever to lift the heavy box.
   科学家使用一个杠杆来抬起沉重的箱子。
3. 3. The doctor applied a small lever to release the patient's airway.
   医生用一个小杠杆来释放患者的气道。