人字梯当一字梯太自信无人监护梯子，是我们生活中经常接触，有的甚至是每天要使用的。移动梯子虽然使用率低一点，但在家中，在单位，有时够不着要爬个高，有时作业需要，也少不了要用梯子。梯子上会摔死人，不少人总不大相信，不就是一、二米高的么，跳一下不就下来了吗？但 Ladder ladder When the ladder is too self-confidence stepping ladder, is our daily contact, and some even use every day. Although the use of mobile ladders is lower, at home, in units, there is sometimes no need to climb a high, sometimes homework needs, and ultimately use a ladder. Ladders will be killed on the ladder, many people do not always believe, is not a one or two meters high, jump about it down? but