Complex sentence: Rajavi served as an organizer of the anti-Shah student movement in the 1970s and in 1979, became an official of the social section of the PMOI/MEK, where she served until 1981.
Split into simpler sentences: Rajavi served as an organizer of the anti-Shah student movement in the 1970s. In 1979, she became an official of the social section of the PMOI/MEK, where she served until 1981.