This is a popular book introducing the principles of relativity.

这是介绍相对论的书,是普及本.

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Most bookstores stock both hard - backs and paperbacks.

多数书店出售有精装和纸皮 普及本 两种书籍.

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Hardback: Book sellers'term to mean case - bound book as distinguish from paper - back . Synonymous with Hard - cover .

精装本: 英文是书商用名词,意指 精装本;以别于 普及本.

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Paper back: Booksellers'term to mean soft - cover book as distinguish form hard - cover book .

普及本: 是书商用名词,意指平装本,有别于 精装本.

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