初学游泳者不得进入深水区，携带救生圈的泳客不得超越浅水区标线。

The beginners should not access the deep end, and the shallow area reticule should not be overstepped by the swimmers with life buoys.

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初学者也许能很容易地掌握蛙泳、自由泳或仰泳，但蝶泳却难得多，对游泳者的技术要求很高。

While other styles like the breaststroke, front crawl, or backstroke can be swum easily even by beginners, the butterfly is a more difficult stroke that requires good technique to be feasible.

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