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daydream; fantasy; fancy; vision
子供の頃は空想の世界で遊ぶのが好きだったな。
I liked playing in a world of fantasy when I was a child.
空想にふけっていないで現実を見なさいと言われた。
I was told not to daydream and look at reality.
彼の話は空想と現実が混じっていて分かりにくい。
His story mixes fantasy and reality and is hard to understand.