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to pollute; to contaminate; to soil; to make dirty; to stain
to disgrace; to dishonour; to dishonor; to defile
工場の廃水で川を汚してはいけない。
You must not pollute the river.
不正は会社の名声を汚す行為だ。
Misconduct is an act that dishonours the company's reputation.
服を汚さないように注意してください。
Please be careful not to stain your clothes.