Complex sentence: He served in several high-ranked positions in the 1990s, prominently as the Minister of Internal Affairs of Armenia from 1992 to 1996 and the Mayor of Yerevan from 1996 to 1998.
Split into simpler sentences: He served in several high-ranked positions in the 1990s. He was the Minister of Internal Affairs of Armenia from 1992 to 1996 and the Mayor of Yerevan from 1996 to 1998.