Original sentence: After the completion of his education Cyril took orders, and seems to have held the important position of chartophylax, or secretary to the patriarch and keeper of the  archives, with some judicial functions also.Besides his native Greek tongue, he was fluent in Latin, Arabic, Hebrew, and Slavonic
Edited sentence: " After the completion of his education Cyril took orders, and seems to have held the important position of chartophylax, or secretary to the patriarch and keeper of the  archives, with some judicial functions also.Besides the Greek tongue of his society, he was fluent in Latin, Arabic, Hebrew; his skills with Slavonic may have been native, for his mother spoke the language of the local Slavs and, according to the Vita, Byzantine Emperor Michael III stated that "all Thessalonians speak perfect Slavonic