Original sentence: Chinese records suggest that the languages of Goguryeo, Buyeo, East Okjeo, and Gojoseon were similar, while Goguryeo language differed significantly from that of Malgal (Mohe).However, no credible theory proposing that Goguryeo's language to be a Sino-Tibetan language has been made; rather, all sides agree that Chinese was only used as an official written script, not as the daily spoken language.The Goguryeo language is unknown except for a small number of words, which mostly suggests that it was similar to the language of Silla and influenced by the Tungusic languages.The government of Goguryeo used Chinese characters (Hanzi/Hanja) for its official documents
Edited sentence: Goguryeo used Chinese characters (Hanzi/Hanja) for its official documents.The Goguryeo language is unknown except for a small number of words