Another finding is that people who are married or work together do not have as much of an effect on happiness as friends do.

VOA: special.2009.01.21

Many people said the problem with general levels of happiness or unhappiness rather, the cause is people have too high expectations.

很多人说,一般的快乐或不快乐水平，是由于人们有过高的期望。

哈佛公开课 - 幸福课课程节选

People have their own definitions of happiness. What does happiness mean to you?

每个人对于幸福都有不同的定义。对你来说，幸福是什么？

幸福的定义 - SpeakingMax英语口语达人

So people change-- up or down in their level of happiness is a result of their experiences.

人们的快乐水平会上下变化,这是他们的经验之谈。

哈佛公开课 - 幸福课课程节选