That force is a drive rod up and down which causes it Power Take-off System to turn a Generator inside the buoy.

这些浮标的原理是海浪的涨潮和退潮的作用，当海水涨潮或退潮时，“动力起飞系统”就可以利用这些能源推动发电机。

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If you are on the inside, you must work your way into that group in order to swim around the buoy (rules generally frown upon swimming to the inside of the turn buoy).

如果你在中间的话，你就得往人堆里挤，才能绕过浮标(通常，规则不会允许你从浮标里面绕过去的)。

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