People in developing countries are happier than before while people in developed countries are no happier than they used to be. Why? What lesson can you learn from it?

话题好像是问为什么在已开发的富国人民不如以前快乐，而相对的，在开发中的人民却是比以前快乐?又问从这种情形学得什么教训?。

youdao

So by the end of these three months semester, you are happier than you were before.

三个月后，期末时，你会变得更快乐。

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