swear offsth
—phrasal verbwithswearverbuk/sweər/us/swer/swore|sworn
to make adecisiontostopdoing, using, or beinginvolvedwith somethingharmful, such asdrugsoralcohol, or something that is not good orhelpful
发誓不做，保证放弃，下决心戒除
Afteryearsofaddiction, hesworeoffdrugscompletely.上瘾几年后，他发誓彻底戒毒。