wèile / yùfáng / jiǎnyābìng / qiánshuǐyuán / bìxū / ànzhào / guīdìng / fēn / jiēduàn / shàngfú

为了预防减压病，潜水员必须按照规定分阶段上浮。

To prevent decompression sickness, divers must ascend in stages according to the regulations.