Complex sentence: The first successful production weapon was the MAS 40 adopted in March 1940.it inherited its system from the SE MAS 35 itself derived from the MAS modele 1928 and the MAS 1928/31.
Split into simpler sentences: The first successful production weapon was the MAS 40 adopted in March 1940. It inherited its system from the SE MAS 35 itself derived from the MAS modele 1928 and the MAS 1928/31.