Sometimes they swam around their tanks casually, whereas at other times they were directed and rewarded by their trainers to swim at their fastest.

有时候它们会偶然地在池底游动，然而在其他时间里它们被训练者指导，并且在它们快速游动时会得到奖赏。

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Excellent pump or bilge, live bait tanks, liquid transfer, de-watering, emptying water beds, clogged sinks, tubs, and other small jobs around the house.

优秀泵或舱底，液体转移，脱水，排空水床，沉积物和其他小厂房任务。

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