HSK 4
组
zǔ名（动量）
to form; to organize; group; team; classifier for sets, series, groups of people, batteries; surname Zu
全班一共有五个组。
Quán bān yí gòng yǒu wǔ gè zǔ.
The class has five groups in total.
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Other HSK words sharing a character
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Appears across levels (4（5）) in the HSK 3.0 word list.