lǎo / shī / xiàng / xué / shēng / jiè / shào / le / chà / qǔ / de / lì / shǐ / hé / yǎn / chàng / tè / diǎn

老师向学生介绍了岔曲的历史和演唱特点。

The teacher introduced the history and performance features of chaqu to the students.