A(n)( )may consist of a single root morpheme as in iron or of two root morphemes as in a compound like handcuff.
【正确答案】：STEM
【题目解析】：本题考查词干。A stem may consist of a single root morpheme as in iron or of two root morphemes as in a compound like handcuff.一个词干可能由单个词根词素组成，如在iron（铁，铁制品）中；也可以由两个词根词素所组成，如在复合词handcuff（手铐）中。故答案为stem。
