Complex sentence: In the early 70's, the Paris Chamber of Commerce and Industry decided to introduce coeducation to all of its schools and since 1973, HEC Paris, ESCP, EAP, and also ESSEC (École supérieure des sciences économiques et commerciales) have been accepting women.
Split into simpler sentences: In the early 70's, the Paris Chamber of Commerce and Industry decided to introduce coeducation to all of its schools. Since 1973, HEC Paris, ESCP, EAP, and also ESSEC (École supérieure des sciences économiques et commerciales) have been accepting women.