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    It's a hot day．A mother crow(乌鸦)and her two kids are flying in the sky．They are very thirsty．So they want to find some water to drink．They find a jar on the ground．There is some water in the jar．But it's not full(满的)．Their beaks(鸟嘴)are too short．They can't drink the water．Little crows don't know how to drink．Mother crow looks at the jar，then she asks her children to put some stones into the jar. Oh, the jar is full now! They can drink water now．How clever the mother is!