Last time we said we had three kinds of texture in music which are: monophonic, homophonic and polyphonic.

上一次我们说过，音乐中有三种织体，单音，主音和复音织体。

Native Americans music in North America is almost entirely monophonic, but there are notable exceptions.

北美印地安人的音乐几乎完全是单声道的，但也有明显的例外。

The earliest medieval music did not have any kind of notational system. The tunes were primarily monophonic and transmitted by oral tradition.

中世纪早期并没有多种记谱法体系，音乐作品主要是单声部的，并依靠口头传播。