Complex sentence: Lieutenant Amdrup was the leader of the 1898-1900 Carlsberg Fund Expedition to East Greenland that identified and examined the then completely unexplored stretch of coast between about 66th parallel north and Scoresbysund at about 70th parallel north.
Split into simpler sentences: Lieutenant Amdrup was the leader of the 1898-1900 Carlsberg Fund Expedition to East Greenland. The purpose of the expedition was to identify and examine the then completely unexplored stretch of coast between the 66th parallel north and Scoresbysund at about 70th parallel north.