3 sentences

1. 磬是属于八音中石类的乐器。

   qìng shì shǔ​yú bā​yīn zhōng shí lèi de yuè​qì.

   The 'qing' is a percussion instrument belonging to the stone category of the 'eight sounds.'

   Source: Dong Chinese Dictionary

2. 这种古老的乐器是用陶土做的，在八音中属于土类。

   zhè zhǒng gǔ​lǎo de yuè​qì shì yòng táo​tǔ zuò de, zài bā​yīn zhōng shǔ​yú tǔ lèi.

   This ancient musical instrument is made of clay and belongs to the 'earth' category among the eight traditional types of instruments.

   Source: Dong Chinese Dictionary

3. 在欣赏古乐时，专家向我们介绍了八音中“金”类乐器的特点。

   zài xīn​shǎng gǔ yuè shí, zhuān​jiā xiàng wǒ​men jiè​shào le bā​yīn zhōng“ jīn” lèi yuè​qì de tè​diǎn.

   While enjoying ancient music, an expert introduced us to the characteristics of the "metal" category of instruments among the eight traditional sounds.

   Source: Dong Chinese Dictionary