strong: may imply power derived from muscular vigor, large size, structural soundness, or intellectual or spiritual resources: a ~ desire to succeed.    （vigor/vigorous活力，指能够长时间地活动，健壮而鲜活）  


stout: suggests an ability to endure stress, pain, or hard use without giving way: wear ~ boots when hiking.   （give way=yield表示物体在压力下变形或人在压力下让步）   结实的靴子


sturdy: implies strength derived from vigorous growth, determination of spirit, or solidity of construction: people of ~ independence.    


stalwart: suggests an unshakable dependability and connotes great physical, mental, or spiritual strength: ~ supporters of the environmental movement.   如stalwart fans忠诚的粉丝，本例环境运动的忠实的支持者


tough: implies great firmness and resiliency: a ~ political opponent.   resilient指有韧性弹性，外力折不断，能恢复原状。tough表示强韧firm and resilient，既结实又有韧性，特朗普有本书叫time to get tough，他对中国的态度可以用tough形容


tenacious: suggests strength in seizing, retaining, clinging to, or holding together: ~ of their right to privacy.     (tenacious坚持to hold onto something like a dog with a bone像狗紧咬骨头一样，可以用于坚持某一要求/理想/目标。这个词来自词根TEN表示抓住to hold，如tenable站得住脚的，tenure任期、终身教授，tenant房客，lieutenant副手中尉，tenet主旨，都来自TEN词根"抓住"）


strong强: 泛指有力量，如体格健硕、心志坚定，stout结实: 能承受压力痛苦和重度使用，sturdy坚强: 身体结实意志坚定成长茁壮，stalwart忠实有力: 形容忠诚可靠，或有很大力量，tough强韧(褒): 既坚强又有韧性，tenacious紧抓坚持: 指用力抓住不放松


记忆方法: 1) 首字母SSSSTT想成试试他<==是否坚强

         2) 坚强的意思是有力量抵抗和承受mean showing power to resist or to endure.首字母SSSSTT想成试试他<==是否坚强