adverbdobhriathar1in deceit, betrayalgo fealltachle feallgo cealgachcmuhe was treacherously killedmaraíodh go fealltach é2dangerouslygo contúirteachcmuthe rocks are treacherously slipperytá na carraigeacha thar a bheith sleamhain agus contúirteachthe road was treacherously icybhí oighear ar an mbóthar a d'fhág an-chontúirteach é
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