frown: implies a stern face and contracted brows that express concentration, bewilderment, anger, displeasure, or contempt: the teachers ~ed on my boyish pranks.  frown皱眉的反义词是smile微笑  (stern严肃严厉，特别指在用权或处罚时stresses inflexibility and inexorability of temper or character，如a stern judge who seemed immune to pleas for mercy一个严厉的法官不愿宽大处理)


scowl: suggests a similar expression that conveys bad humor, sullenness, or resentful puzzlement: a grumpy old man who ~ed habitually.  （sullen表示生闷气，不愿说话，不愿交往或配合implies a silent ill humor and refusal to be sociable or cooperative，如remained sullen throughout the party整个晚会上都在生闷气，在2018-04-17 不快sullen-gloomy）  又如he wore a permanent scowl on his face他终日面带怒容


glower: implies a direct defiant brooding stare or glare as in contempt or defiance: the natives merely ~ed at the invading tourists.（brood这里指一直盯着或瞪着，原意是母鸡孕育小鸡，一窝小鸡，比喻长期怀有想法，如he brooded over his dead mother他对已故母亲念念不忘，如for years he brooded vengeance/suicide多年来他一直在盘算报仇/自杀，如a brood of chicks一窝小鸡，可用于人，如a mother and her brood母亲和一窝孩子，如a remarkable brood of writers几位优秀作家） glower原意是stare凝视盯，但现在主要表示glare瞪了


lower: suggests a menacing darkness or gloomy anger and refers either to persons OR to skies that promise bad weather: ~ed as he went about his work, never uttering a word.         又如a day of lowering clouds一天阴云，如to lower price/volume/coffin/flag降低价格/音量/棺材/旗


frown皱眉: 指表情严肃眉毛缩紧，可表示多种情感，如专注困惑愤怒不快轻蔑，scowl怒容绷脸: 表情类似，但表示心情差生闷气或带怨恨的困惑，glower瞪: 指长时间地瞪眼，表达轻蔑或抗拒，lower沉脸天阴: 表示面色阴沉甚至带怒容，可指人面色差或天气差


记忆方法:  1）首字母FSGL凡事过了过犹不及<==怒容            

         2）怒容的意思是脸色阴暗面带威胁mean to put on a dark or threatening countenance or appearance.