Finally, instead of trying hard to be happy, as if that were the sole purpose of life, I will try still harder to make others happy.

最后，我不会竭力为自己谋幸福——似乎那是人生惟一的目标；与之相反，我会更加努力，让他人幸福。

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Finally, instead of trying hard to be happy, as if that were the sole purpose of life, I would, if I were boy again, try still harder to make others happy.

最后，假如我再回到童年，我不会竭力为自己谋幸福——似乎那是人生的唯一目标；与之相反，我会更加努力，让他人幸福。

youdao

Finally, instead of trying hard to be happy, as if that were the sole purpose of life, I would, if I were a boy again, try still harder to make others happy.

最后，假如我又回到了童年，我不会力图为自己谋幸福，好像这就是人生唯一的目的；与之相反，我要更努力为他人谋幸福。

youdao