backstep welding sequence

例句：

1. 1.The team backstepped to avoid a collision.
   队伍后退以避免碰撞。
2. 2. As the sun set, the sky slowly backedstepped.
   随着太阳落山，天空慢慢后退。
3. 3. The car backedstepped into the parking lot.
   汽车缓缓后退进入停车场。