Complex sentence: If Shepard has sufficiently high EMS, the surviving Normandy members hold a memorial service for him/her, with Shepard's love interest placing Shepard's name on the memorial wall (Control), and also comforting EDI (Synthesis).
Split into simpler sentences: If Shepard has sufficiently high EMS, the surviving Normandy members hold a memorial service for him/her. If one of the members is Shepard's love interest, they will place Shepard's name on the memorial wall (Control), and also comfort EDI (Synthesis).