This bulky piece acts a bit like a ratchet; the wheel requires some vibrational energy to get past it.
这个大型零件功能有点儿像防倒转的棘齿；轮子需要振动能来帮助前行。
2
It forms these arches because when the wheel has rotated by a full turn, then you're basically back at the same situation, except a bit further along the route.
它形成这些拱形，是因为车轮完整的转动了一圈，然后就回到了原处，除了移动了一段路径。
3
After you are done with talking to your plant and nurturing it for a bit, you simply stow your tools there and wheel it back to the greenhouse.