In inviting some of its undergraduates back to campus for the fall semester, MIT will prioritize seniors — to allow them to progress toward completion of their degrees in 2021 — as well as others who need to be on campus, or who require in-person instruction, to succeed in their coursework. Across the board, undergraduate costs for the coming academic year will be reduced substantially: Tuition will be held at last year’s level, eliminating a planned 2020-21 increase announced earlier, and undergraduates will receive a $5,000 grant to offset their…