In different working conditions, fast, slow walk, only one person can be in the air continuously complete upper and lower, forward and backward, turning all the action.

能够在不同工作状态下，快速、慢速行走，只需一个人操作便可在空中连续完成上下、前进、后退、转向等所有动作。

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Fast forward twenty years, and to walk the streets of any city in the U.S. is to see Americans of all income classes listening to music, texting, searching internet sites, and watching television on small rectangular objects that also serve as the once much coveted wireless phone.

FORBES: The Life Enhancing, Unrelenting Brilliance of Income Inequality