lever harrow

例句：

1. 1. The car is so heavy that it needs a strong lever to move it.
   这辆车太重了，需要一把强有力的杠杆才能移动。
2. 2. He used a lever to lift the heavy box.
   他用一个杠杆把沉重的箱子抬起来了。
3. 3. The scientist used a lever to measure the force of gravity.
   科学家用一个杠杆来测量重力的力量。