1. 流氓：toughen 变坚韧 | toughie 流氓 | toughly 坚强地

2. 粗暴的人：toughen /变顽固/锻炼/ | toughie /粗暴的人/ | toughness /韧性/有粘性/强硬/强健/

noun

1. a particularly difficult or baffling question or problem

Synonym: poserstumpersticker

2. an aggressive and violent young criminal

Synonym: hoodhoodlumgoonpunkthugtoughstrong-armer