Complex sentence: He was also took part in politics and was an active member of Justice Party; he served as the General Secretary of the party till 1940 after which C. N. Annadurai took over.
Split into simpler sentences: He was also took part in politics and was an active member of Justice Party. He became the first General Secretary of the party, a position which he continued to hold till 1940 after which C. N. Annadurai took over.