是同一词根的词.
health是名词.healthy是形容词,healthily是副词.
形容词修饰名词,副词修饰动词.
答案：
三组这类的单词：
success-successful-successfully
interest-interested-interesting
surprise—surprised—surprising
还有剩下的题,你就按照这个来好了,看你猛的水平咯~
care(n./v.);careful(adj.);carefully(adv.) danger(n.);dangerous(adj.)