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彼は一冊の本を読みました。
He read one book.
A unit of measurement for books or documents, equivalent to one volume or a certain number of pages.
この本は3冊あります。
There are three volumes of this book.
Often used to count books, documents, or manga.
Use 冊 to count books, manga, or bound documents. Example: 1冊 (ikisō), 2冊 (nisō), 3冊 (sansō).
From Chinese '册' (cè), meaning 'book' or 'register'.
Used to count bound written works. Does not apply to e-books or loose papers.