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一位精明的家庭主妇听人说有一种炉子用起来可以比她现在用的炉子省一半的煤。她听了大为兴奋,说:“那太好了!一个炉子可以省一半的煤,那么如果我买两个炉子的话不就可以把煤全都省下来了吗?”
A shrewd housewife heard of a stove that could save about half the coal of her current stove. She listened greatly excited and said: “That’s great! A stove can save half of the coal, so if I buy two stoves, I can save all the coal?”