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class (of students)
group (of people); party; team; crew
lot; bunch; set
crime family; organized-crime syndicate
set (of items); assortment; deck (of cards); pack
typesetting; composition
三年二組の教室は廊下の奥にあった。
I went to Class 2 of third grade.
組ごとに分かれて清掃作業をした。
We worked divided into groups.
うちの子は一年三組だ。
My child is in Year 1, Class 3.