The chief function of ()is not to change the word class of the s

The chief function of ()is not to change the word class of the stem, but to change its meaning.
A、prefixes
B、suffixes
C、morphemes
D、​varieties
【正确答案】:A
【题目解析】:前缀的主要功能不是改变词干的词类,而是改变它的意义。