lǎo / shī / zài / kè / shàng / jiè / shào / le / liù / cháo / sì / dà / jiā / de / yì / shù / chéng / jiù老师在课上介绍了六朝四大家的艺术成就。The teacher introduced the artistic achievements of the Four Great Painters of the Six Dynasties in class.