Rúben Amorim has received so much coverage since being linked to the Manchester United job that most people know the manager has mostly played a 3-4-2-1 formation throughout his career. Given that presumably Manchester United have done their homework on him, this raises the question of how the players in the current United squad might fit that system -- a scheme United haven't really used except in one-off situations.
Of course, the club can turn to the transfer market and acquire players that fit a 3-4-2-1 formation, or who they think are simply better than the ones already there.