Complex sentence: Students may enroll full or part-time, and classes may be taken on campus, via the Internet, or both, but in order to earn an academic degree, students must complete a minimum number of on-campus-only credits at Harvard.
Split into simpler sentences: Students may enroll full or part-time, and classes may be taken on campus, via distance-learning, or both. In order to earn an academic degree, students must complete a minimum number of on-campus-only credits at Harvard.