in a world of your own/in your own little worldused to say that someone seems to spend a lot of time thinking or imagining things, and does not seem to notice what is happening around them 生活在自己的(小)天地里 She was a shy child who seemed to live in a world of her own. 她是个腼腆的孩子,似乎生活在自己的世界里。
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