Other famous blunders by Yanukovych are his claim that Anton Chekhov was "a Ukrainian poet" in January 2010, forgetting on 6 January 2011 to congratulate the Greek-Catholic Ukrainian community, which, along with the rest of the Ukrainian people, celebrates Christmas that day, and confusing Kosovo with Serbia and Montenegro, and North Ossetia with South Ossetia in March 2010. Over the years, Yanukovych's proficiency in the Ukrainian language has noticeably improved. (In a form filled in for the 2004 election he claimed to be fluent in Ukrainian, yet made in the very form a series of egregious mistakes, inter alia writing his own wife's patronym wrongly).