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      Books are our greatest friends. They 1us stories of every country in the world. They give us all kinds of 2 . Life is short. One can not know and see 3 in the world. 4 the help of books, one is able to know what happened thousands of years ago and 5 is happening in every part of the world now. Books give us not only knowledge 6  pleasure. Reading good books is the best way of7    our free time. And many beautiful stories for children are 8and full of wisdom(智慧).
    All the great men 9 books. Knowledge from books helps them to succeed, because books are the source(源泉)of knowledge and knowledge is the source of  10 .

先化简，再求值：（ $\frac{x^2-2x+4}{x-1}$ +2﹣x）÷ $\frac{x^2+4x+4}{1-x}$ ，其中x满足x²﹣4x+3=0．