Daily Chinese Idiom Guessing Game
Using a cup of water to put out a cartload of burning firewood; an utterly inadequate effort to solve a large problem.
用一杯水去救一车着了火的柴草。比喻力量太小，解决不了问题。
《孟子·告子上》今之为人者，犹以一杯水救一车薪之火也。”
His small donation was like a drop in the bucket, a case of cup of water to a cartload of firewood.