Lǎo / shī / xiān / xiàng / xué / shēng / jiè / shào / qī / xián / qín / de / lì / shǐ / rán / hòu / yǎn / zòu / le / yì / shǒu / gǔ / qǔ

老师先向学生介绍七弦琴的历史，然后演奏了一首古曲。

The teacher first introduced the history of the guqin to the students and then played an ancient piece.