earn one's keep
Justify one's presence
To earn one's keep is to contribute enough to justify the resources you consume—originally room and board, now any form of support.
A farmhand earns his keep through labor; a house cat earns hers by catching mice.
The phrase often appears when questioning whether someone or something provides sufficient value: That old truck barely earns its keep anymore.
contribute
Give to a collective
provide · help · assist · serve · participate · pull one's weight · chip in · pitch in · cooperate · collaborate
prove
Establish as fact
validate · worth · value · demonstrate · show · repay · compensate · fulfill · deliver · perform
earn one's keepsponge
Absorbent cleaning material
leech · mooch · freeload · scrounge · take advantage
earn one's keepslack off
Reduce one's effort
loaf · idle · laze about · coast · do nothing
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