Crossword Clue:

to act as a substitute

AnswerCrossword Clue
PAPAYASFruits whose seeds can act as a substitute for black peppercorns
INSTEADAs a substitute
LIEUIn... of (as a substitute for)
AMOLERoot used as a soap substitute
ASKAct as a quizmaster
ABETAct as a lookout
LIAISEAct as a go-between