In the 3 - best in swimming breaststroke, buoyancy to the baby more rotation space.
游泳- - -最好是蛙式，浮力给宝宝更多转动的空间。
youdao
The second hollow space receives a rotation shaft.
第二空腔承接转动轴。
应用推荐
模块上移
模块下移
不移动