Complex sentence: Năsturel was primarily an advocated of Old Church Slavonic, the courtly language, being one of its last exponents in Romanian literature, and teaching it to students at the school in Târgoviște.
Split into simpler sentences: Năsturel was primarily an advocate of Old Church Slavonic, the courtly language. He was one of its last exponents in Romanian literature, and taught it to students at the school in Târgoviște.