Complex sentence: Iran Air, branded as The Airline of the Islamic Republic of Iran ("Havâpeymâyiye Jomhuriye Eslâmiye Irân"), is the national flag carrier airline of Iran headquartered on the grounds of Mehrabad Airport in Tehran.
Split into simpler sentences: Iran Air, branded as The Airline of the Islamic Republic of Iran ("Havâpeymâyiye Jomhuriye Eslâmiye Irân"), is the flag carrier airline of Iran. It is headquartered on the grounds of Mehrabad Airport in Tehran.