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shichi-go-san; 7-5-3 day; festival day for children aged 7, 5 and 3 held on or around November 15
lucky numbers 7, 5 and 3
「七五三」 has another reading with different meanings.
七五三で着物を着た写真を撮った。
We took photos in kimono for Shichi-Go-San.
七五三は子供の成長を祝う行事だ。
Shichi-Go-San celebrates children's growth.
七五三の千歳飴をもらった。
I got chitose candy for Shichi-Go-San.