下面（）文件属于声音媒体文件。 A: abc.txt B: sound.mid C: xyz.wav D: ab.tif

下面（）文件属于文字媒体文件。 A: abc.txt B: sound.mid C: xyz.doc D: ab.wps

已知三阶矩阵$A$满足$\mid A-E\mid=\mid A-2E\mid=\mid A-3E\mid=0$，则$\mid A\mid$=( )。 A: $4$ B: $6$ C: $12$ D: $3$

设$A,B$是$n$阶正交矩阵，且$\mid A\mid=-\mid B\mid$，则( ). A: $A+B$可逆 B: $A+B$不可逆 C: $\mid A+B\mid=1$ D: $\mid A+B\mid=-1$

In the historical development of language, sound change is inevitable, such as sound loss, sound a______ and sound movement.

A sound mind is inseparable from a sound body. The word “sound” means______.

That ____ quite interesting. A: aren't sound B: don't sound C: isn't sound D: doesn't sound

8.Primary _________means the direct imitation of sound by sound, of natural sound by human speech sound.

Simultaneous or overlapping articulations, as when the nasal quality of a nasal sound affects the preceding or following sound so that the latter becomes nasalized. If the affected sound becomes more like the following sound, it is known as anticipatory ; if the sound shows the influence of the preceding sound, it is perseverative .​​​​

(Multiple Choice) When the volume changes, the amount of sound change is equal in both the approaching sound and the receding sound, which one is more noticeable?（ ） A: the receding sound B: the approaching sound C: both of them