“…At the MorphoRuEval-2017 shared task [11], a 96.91% accuracy score in lemmatization was achieved on a balanced set of data from various sources (news, social networks, fiction, etc.). And in the GramEval-2020 shared task [12] the track became even more complicated since data from social media, poetry and historical texts of the 17th century were added to the test sample: the best overall lemmatization score being 98% on fiction texts, 98.2% on the news, 95.3% on poetry, 96% on social media, 93% on wiki and 78.3% on historical texts. It became manifest that it is technically possible for the Russian language to pose more complex challenges, especially for notoriously "difficult-to-process" groups of words and lexical categories.…”