Complex sentence: In 1925 Meller together with Sonia Terk, Alexandra Exter, Nathan Altman participated in "Exposition Internationale des Modernes" ("Art Deco)" in Paris where he was awarded a gold medal for the scenic design of the Berezil theater.
Split into simpler sentences: In 1925 Meller together with Sonia Terk, Alexandra Exter, Nathan Altman participated in "Exposition Internationale des Modernes" ("Art Deco") in Paris. There Vadim Meller was awarded a gold medal for his scenic design of the Berezil theater.