不知后半
Not knowing the second half
以上为机器翻译结果，长、整句建议使用 人工翻译 。
一般都会对不能像精通其他运动一样掌握游泳很沮丧。这种沮丧感有时很强烈，(后半句不会，不知指什么)！
Generally quite frustrated that they are not as proficient at swimming as in other sports. Sometime this frustration is very strong and is bubbling just below the surface!
youdao
应用推荐
模块上移
模块下移
不移动