Close your book, please.

请把书合上。

《新英汉大辞典》

Close your book and write one word or two on a piece of paper.

合上你的书，在纸上写下一两个字。

youdao

Open your pencil box, close your book and carry your bag.

打开你的铅笔盒，合上你的书然后背上你的书包。

youdao

The cost to produce an e-book version of an existing book is close to nothing.

FORBES: How Not to Price an e-book

Close on the heels of the launch of its e-book store in Brazil, Amazon announced the launch of its Kindle e-book store in China last Thursday.

FORBES: Amazon Can Drive Big Kindle Growth With China Launch

In fact, the only thing likely to seriously vex you is the foreboding cliff-hanger Rowling leaves you to contemplate as you close the book.

CNN: Books - Review: Gladly drinking from Rowling's 'Goblet of Fire'