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one-yen book (Showa period)
古本ふるほん屋やで円本えんぽんを見つけみつけた。
I found a one-yen book at the used bookstore.
円本えんぽんを収集しゅうしゅうするのが趣味しゅみだ。
Collecting one-yen books is my hobby.
祖父そふの蔵書ぞうしょに円本えんぽんがあった。
There were one-yen books in my grandfather's collection.