The ______ of language can be grouped and regrouped into a large

The ______ of language can be grouped and regrouped into a large number of units of meaning such as morphemes and words, which are found at the higher level of the system.
A、vowels
B、sounds
C、words
D、consonants
【正确答案】：B
【题目解析】：The sounds of language can be grouped and regrouped into a large number of units of meaning such as morphemes and words, which are found at the higher level of the system.