expensive：adj.昂贵的；花钱多的；价格高的；
expense：n.费用；价钱；花钱的东西；vt.向…收取费用
I don't think you appreciate how expensive it will be.
我想你不了解它会有多昂贵。
Admittedly, it is rather expensive but you don't need to use much.
它的确很贵，但不需要用得很多。
Many foreign goods are too expensive for American pocketbooks.
许多外国货都太贵，与一般美国人的财力不符。
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