Complex sentence: Wilson attended Davidson College in North Carolina for the 1873--1874 school year, cut short from illness, then transferred to Princeton as a freshman when his father began teaching at the university.
Split into simpler sentences: Wilson attended Davidson College in North Carolina for the 1873--1874 school year. After medical ailments kept him from returning for a second year, he transferred to Princeton as a freshman when his father took a teaching position at the university.