 Complete the following phrase:  Boyarsky participated in the establishment of the USSR Trade Unions. In 1921-1924 he was the chairman of the Smolensk Governorate Committee of Professional Unions, in 1924-1925 he occupied similar posts in Orenburg and Kazakh Committees, in 1926-1928  in Kazan, in 1928-1929  in Samara. Since the 