有一天他偶然发现了埃玛的日记，便开始读了起来。
有一天，他们偶然从收音机里听到了有关高加索石室冢墓的故事，于是决定去那里。
One day, they accidentally heard on the radio the story about the dolmens on the Caucausus and decided to go there.
偶然的一天，他们在广播里听到了关于高加索地区石棚的故事，好奇的他们决定去那里，一探究竟。
But one day they accidentally heard on the radio the story about the dolmens on the Caucausus and decided to go there.
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