Sound is caused by vibrations. A vibration is a back and forth movement.

声音是由振动引起的。振动就是往复运动。

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The back and forth movement of the image's colors guides our eyes and spirits to produce a flow. In Hong Ling's paintings, far-reaching visuals are not the factors that move people.

画面中色彩的前后运动，引导我们的眼睛和心灵产生流动，在洪凌的画里打动人的不是一种视觉的深远。

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Generally, the reason for such seasonal back-and-forth movement is to seek resources that aren't available within a single area year-round.

一般来说，进行这种季节性往返迁移是为了寻找在一个地区无法全年获得的资源。

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For Empson, there's a kind of a fluid and easy movement back and forth between what for hermeneutics are three very different phenomena: author, text, reader.

对Empson来说，在作者，文本，读者之间,诠释学里认为这是三种非常不同的现象：,在三者之间有一种流畅的反复的关联。

耶鲁公开课 - 文学理论导论课程节选

Assuming the continued movement of gold back and forth between countries, in a free market situation no country would ever run out of gold.

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This erratic stock movement was due in part to a back and forth over whether it's actively engaged in merger talks with JPMorgan Chase.

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