单项选择题
A.A locutionary B.An illocutionary C.A perlocutionary D.A speech
The great source of modification of the air stream is f...
单项选择题The great source of modification of the air stream is found in the（）cavity.
A.nasal B.oral C.lung D.glottis
Which of the following sounds is a voiceless bilabial s...
单项选择题Which of the following sounds is a voiceless bilabial stop?（）
A.[p] B.[b] C.[m] D.[t]
