Complex sentence: In his time Li was recognized as the most erudite person with regard to Song Dynasty poetry, and is considered a leader of the Zhejiang School of poetry (also known as Western Zhejiang School of Lyrics), started by Zha Shenxing and Zhu Yizun.
Split into simpler sentences: In his time Li was recognized as the most erudite person with regard to Song Dynasty poetry. He is considered a leader of the Zhejiang School of poetry (also known as Western Zhejiang School of Lyrics), which was started by Zha Shenxing and Zhu Yizun.