用超声波探测器可以定位鱼群，渔民们准备一种特别的装置：看起来象连着扶手的陀螺。

With help of a sonic depth-finder a proper shoal gets detected and the fishermen prepare special devices which look something like spinnings and attached to the handrails.

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电子探测器追踪到了鱼群。

Electronic detectors tracked down schools of fish.

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电子探测器追踪到了鱼群。

Electronic detectors tracked down schools of fish.

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