If the load slips or your lever collapses, the victim may be injured even more.
如果负载滑落或杠杆折断，被救援者可能会受到更大伤害。
2
The force needed at one end of the lever to move the load at the other end of the lever depends on the distances to the pivot.
杠杆的一端所需要的、去移动另一端的东西的力，取决于与支点的距离。
3
The optimum programme can be used to design four-connecting lever pneumatic roof-window mechanism of all kinds of multi-span plastic greenhouses by changing load and structure parameters.