Complex sentence: Chiêu Hoàng was only six at that time so every important decisions in royal court were made by Trần clan, profiting this circumstance, Trần Thủ Độ arranged a marriage between Chiêu Hoàng and Trần Cảnh, the eight-year-old son of Trần Thừa.
Split into simpler sentences: Chiêu Hoàng was only six at that time so every important decision in the royal court was made by the Trần clan. Profiting from this circumstance, Trần Thủ Độ arranged a marriage between Chiêu Hoàng and Trần Cảnh, the eight-year-old son of Trần Thừa.