"Happiness is sometimes simple" 可以用英语表达为 "Happiness can be simple at times."

这个短语来源于英语中对幸福的定义。幸福被认为是一种内心的感受，有时可能是由简单的事物引起的，而不需要复杂的条件。

例句:

"I've learned that happiness can be simple. A walk in nature, a good conversation with a friend, or just a quiet moment to myself can bring me a lot of joy." (我已经明白了幸福有时很简单。在自然中散步，和朋友聊天，或只是一个安静的时刻都能给我带来很多快乐。)
"In a world where we are constantly chasing after more, it's important to remember that happiness can be simple." (在我们不断追求更多的世界里，记住幸福有时很简单是很重要的。)
"I used to think that happiness was something that could only be achieved through achieving my goals, but I've reapzed that simple things pke spending time with loved ones can bring me just as much happiness." (我曾经认为幸福只能通过实现我的目标来实现，但我已经意识到像与亲人在一起这样简单的事情也能给我带来同样多的幸福。)