I was heartsick, for I felt that the splendid years of my carefree childhood had come to an end.

我很难过，因为我觉得我无忧无虑的美好童年生活结束了。

《柯林斯英汉双解大词典》

Her birth, and carefree childhood in France.

她在法国出生，以及无忧无虑的童年。

youdao

The carefree childhood became a thing of the past.

无忧无虑的童年已经是过去时了。

youdao

Jo began piano and singing lessons early, but says she missed out on a conventional carefree childhood.

CNN: December 17, 2012 -- Updated 1437 GMT (2237 HKT)

Apart from the work, Tsujihara had a relatively carefree childhood.

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They can never grow up with the sweet naivety that makes childhood carefree.

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