Complex sentence: This encouraged Tillenius and he persevered to redevelop his painting skills using his left hand with further tutelage of a fine artist and great friend, Alexander Musgrove, who established the first drawing school in Manitoba.
Split into simpler sentences: This encouraged Tillenius to persevere and to redevelop his painting skills using his left hand. He received the tutelage of a fine artist and great friend, Alexander Musgrove, who established the first drawing school in Manitoba.