big dipper (switchback), up-and-down-hill track (switchback)
【电学】上下坡轨迹 (z形变角)
up-and-down-hill track (switchback)
暂无补充释义。
up-and-down-hill track (switchback)
暂无补充释义。
big dipper (switchback), up-and-down-hill track (switchback)
up-and-down-hill trackway for toys
up-and-down-hill trackway toy