In pre-Classical Greece, for instance, people "corrected" official calendars by shifting dates forward or backward to reflect the change of season.

例如，在前古典时期的希腊，人们通过前后移动日期来“修正”官方日历，以反映季节的变化。

youdao

And now since it's reversible, we can run it forward or backward.

因为它是可逆的，所以可以正方向运行。

youdao

"It gives you a point to work forward or backward from," Thompson explains.

汤普森解释道，“问清楚了，也好给自己一个时间定位，是向前还是向后。”

youdao

Here,he uses a set of buttons attached to a computer to make the silent robot move forward, backward or around in circles.

VOA: special.2009.12.17

And now since it's reversible, we can run it forward or backward.

因为它是可逆的，所以可以正方向运行。

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If that's all it knows, then in that scenario there is no building or anything else; it continues a trajectory both forward in time and backward in time, and it says that whatever seconds, one second before you set your clock to 0, it would've been on the ground.

如果是这样,在那种模式下,没有楼房或者别的什么,物体的运动轨迹可以沿时间可以向后延伸,也可以向前延伸,不管时间取什么值,在零点前一秒时,物体就在地面上

耶鲁公开课 - 基础物理课程节选

Tapping once on a book opens it for viewing and you swipe forward or backward to turn pages.

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Still, it was a neat trick to flip instantaneously to any frame in the movie and watch the action unwind either forward or backward.

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Dragging the slider jumps forward or backward in the song.

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