女子50米自由泳 Women's 50m Freestyle

男子50米蝶泳预赛 Men's 50m Butterfly Final

在被冻住的时候滑行50米 Slide 50meters while frozen ; Slide 50 meters while frozen

防水深度50米 Water resistant to 50m

男子50米自由泳 Men's 50m Freestyle

步行50米 walk for 50 meters

生活防水50米 WATER RESISTANT 50M

这口井深50米 The well depth 50