Using buttons, you can move forward or backward in time, to go back to any date and time in the past and return to the current time.

通过按钮能够在时间上前移或后移，能够回到过去的任意时间点，并且能够回到当前的时间点。

youdao

Subsequent invocations move the iterator backward or forward by the required distance.

后续的调用会将迭代器前后移动指定的距离。

youdao

Users can move forward or backward in time to see where the hurricane has been—and where it’s headed.

用户可以按时间顺序前后推移，以查看飓风曾经到过哪里，将要到哪里去。

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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