What he concluded was, these pigeons were trying to figure out what makes those pieces of corn come and they started to think well,they had to get the interval between corns right to make this work.

他总结出这些鸽子都在绞尽脑汁,想知道玉米从那来的,它们只能利用,那15秒的间隔去想清楚这个问题

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And so, there is the distinction between fixed schedules versus ratios, variable schedules and ratio versus interval.

因此，在固定时程与变化时程之间,以及在比率与间隔之间，存在着一些区别。

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