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one-year-old
娘むすめは今日きょうで一いち歳さいです。
My daughter is one year old today.
一いち歳さいの子供こどもが元気げんきに遊ぶあそぶ。
A one-year-old child plays energetically.
一いち歳さいの誕生たんじょう日ひを盛大せいだいに祝っいわった。
We celebrated the one-year-old's birthday grandly.