Forward and back and forward and back and forward and back and forward and back.

前进、后退、前进、后退、前进、后退、前进、后退。

(Kush): We are running back and forward.

（库什）：我们正在来回奔跑。

Two white rectangles batting a square ball back and forward as players attempted to win points off each other.

两个白色长方形来回击打一个方形球，玩家试图从对方身上赢分。

Idle children attached themselves to his footsteps, and trotted after him back and forward between the hotel and the office.

。 无所事事的孩子们跟着他的脚步， 跟着他在旅馆和办公室之间来回穿梭。

That's very much a comforting behavior, and even though the person on the left has both moved back and forward, there was no reciprocity.

这是一个非常给人以安慰的行为，即使左边的人前后移动，他们之间并没有动作互换。

A " wheelchair" is a seat with round wheels on them (I guess most wheels would be round, right? )that allow the person in the chair to move back and forward.

“轮椅” 是一种带有圆形轮子的座椅（我想大多数轮子都是圆形的， 对吧？ ），让坐在椅子上的人可以前后移动。

Each player is there hitting the ball across back and forward to each other, so if the ball is in your court, the ball has come over to you, you have to try to return it.

每个球员都在那里互相击球，所以如果球在你的球场上， 球已经传给你了， 你必须试着把它还回去。