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to be mixed; to be blended with; to be combined
to associate with; to mingle with; to interest; to join
白髪が黒髪に交じり始めて年を感じる。
Gray hairs started mixing in with black hair.
笑い声に泣き声が交じっていた。
Crying was mixed in with laughter.
真実に嘘が交じっているようだ。
It seems lies are mixed with the truth.