The curtain is tensioned between two rollers which pull the slit across the film at various speeds.

帘布被绷紧在两个卷轴之间，卷轴能使长条形狭缝以不同的速度沿卷片方向运动。

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The curtain is tensioned between two rollers which pull the slit across the film at various speeds.

帘布被绷紧在两个卷轴之间，卷轴能使长条形狭缝以不同的速度沿卷片方向运动。

youdao