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system
lineage; ancestry; family line
group (e.g. of colors) (colours); family (e.g. of languages); party; school (of thought)
close (evolutionary) relationship
a population sharing a common ancestor (in genetics); strain (e.g. bacterial)
この駅は二つの系統が通っている。
Two lines run through this station.
彼は王家の名門の系統を継いでいる人物だ。
He inherited a prestigious lineage.
分かりやすく系統立てて説明してください。
Please explain systematically.