fill in for
- substituteReplacement for another
- replacePut something else there
- coverProtect by overlaying
- stand-inTemporary human placeholder
- pinch-hitSubstitute in baseball
understudy · backup · temp · relief · proxy · deputy · step-up · sub · interim · placeholder · swap · temporary · emergency · last-minute · bench · reserve · swing · fill-in
presence/absence
fill in forabandon
Leave behind permanently
vacate · leave in the lurch · desert · walk out on · neglect