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act; deed; one's doing
cause; reason
疲れつかれの所為せいか頭痛ずつうがひどくて辛いつらい。
My headache is bad, maybe because of fatigue.
雨あめの所為せいで試合しあいが中止ちゅうしになった。
The game was cancelled because of rain.
風邪かぜの所為せいで声こえが出でなかった。
I couldn't speak because of a cold.