【正确答案】:
MORPHEMES CAN BE GROUPED INTO FREE MORPHEMES AND BOUND MORPHEMES. BOUND MORPHEMES INCLUDE TWO TYPES: BOUND ROOT AND AFFIX. 
【题目解析】:语素可以分为自由语素和粘着语素。粘着语素包括两种类型:粘着词根和词缀。
MORPHEMES CAN BE GROUPED INTO FREE MORPHEMES AND BOUND MORPHEMES. BOUND MORPHEMES INCLUDE TWO TYPES: BOUND ROOT AND AFFIX.