【正确答案】正确答案：Root is that part of a word-form that remains when all the inflectional and derivational affixes have been removed. Thus in the word undesirables, the root is desire. Stem is the part of a word-form that remains when all inflectional affixes have been removed. So in the word undesirables, the stem is undesirable. The stem of a word may be: a) a simple stem consisting of only one morpheme or root, e. g. work; b) a root plus a derivational affix, e. g. worker; c) two or more roots, e. g. workshop.