Lì / shǐ / kè / shàng / lǎo / shī / jiè / shào / le / Xiān / bēi / zú / de / qiān / xǐ / hé / fā / zhǎn

历史课上，老师介绍了鲜卑族的迁徙和发展。

In history class, the teacher introduced the migration and development of the Xianbei people.