【正确答案】Inflectional morphemes indicate grammatical relations by adding inflectional affixes, such as number, person, finiteness, aspect and case; and When inflectional affixes are added, the grammatical class of the stems (to which they are attached) will not change. For instance, car/cars, open/opened, boy/boy's.
(a)"-'s" in teacher's (case)
(b)"-ing" in snowing (aspect)
(c)"-est" in newest (degree)
(d)"-ed" in jumped (tense)

【答案解析】[解析] 本题考查形态学领域涉及的重要概念——曲折语素。