大方廣佛華嚴經疏 19.10

19.10

三語具十事，初一語體；次五語緣，謂風觸七處而出於聲，此略無臍輪牙齒；後吐納等四是辨語相。十事望業皆是語體，此唯無記，故非梵行。

Third, the ten matters of the vocal apparatus: the first one is the vocal essence; the next five are the conditions of speech, namely the wind contacting seven places to produce sound—here the navel wheel and the teeth are omitted for brevity; the final four, such as expelling and taking in, distinguish the marks of speech. In view of karma, these ten matters are all the essence of speech; this is solely indeterminate, and therefore is not pure practice.