When the obstruction is partial and the air is forced through a narrow passage in the mouth so as to cause definite local friction at the point, the speech sound thus produced is a ______.
A、fricative
B、affricates
C、nasals
D、liquids
【正确答案】：A
【题目解析】：When the obstruction is partial and the air is forced through a narrow passage in the mouth so as to cause definite local friction at the point, the speech sound thus produced is a fricative. 参见教材P23、24。