The sounds are often made up in the studio because it isn't possible to record them in the wild.

这些声音通常在录音棚里制作，因为很难再野外录下它们。

youdao

ANNOUNCER: so it seems that the voice can operate like a silent movie as a sequence of wordless gestures or a face made up of sounds.

播音员：因此，就像无声电影一样，人类声音似乎也可以看作是由声音符号组成的一系列无言的手势或表情。

youdao

It is reported that the lyrics are mostly made up of weird and bizarre poultry sounds.

据称，这些歌词确实是由奇怪的、诡异的家禽声音组合而成的。邝。

youdao

Up close,it is made up of individual sounds and instruments.

VOA: special.2010.03.24

Birdsong works because it's stochastic, made up of lots of random sounds.

BBC: The surprising uses for birdsong