forge v.伪造～ a famous painter’s signature
flexible a.灵活的 The dancer’s body is very ～.
feasible a.可行的
fertile a.肥沃的
flourish v.茂盛，繁荣
fragment n.碎片
furnish v.提供，配置
fascinate v.迷住
feeble a.虚弱的=weak/faint
flaw n.缺陷 I can’t find a ～，the painting is perfect!
fluctuate n.波动
foster a.培养=develop/nurture/cultivate/领养>～ a child
fragile a.易碎的;脆弱的
furious a.暴怒的