"As long as you're happy, that's all that matters"是表达"你开心就行的"这个意思的常用说法。这句话的来源可能源于英语文化中对幸福的重视。在英语中，人们通常认为，只要个人感到快乐和满足，就能使其他人也感到快乐和满足。

这句话可以用来安慰担心或担忧的人，或者是对某个人做出的选择表示认可。

下面是一些例句：

"I know you're worried about your grades, but as long as you're happy and enjoying your studies, that's all that matters." (我知道你担心你的成绩，但只要你开心并享受学习，就是最重要的了。)
"I know your parents want you to become a doctor, but if being a musician makes you happy, then that's what you should do." (我知道你的父母希望你成为一名医生，但如果当音乐家让你开心，那你就应该这样做。)
"I don't care if people think I'm weird or different. As long as I'm happy, that's all that matters to me." (我不在乎别人认为我奇怪或与众不同。只要我开心，就是最重要的。)