My bookshelves are full of dust — and with good reason. When it comes to cleaning that part of my home, I suffer from the most serious case of avoidance (回避反应症).
The thing is this: when I do set out to clean and re-organize my books, which seldom happens, I place myself into a really bad situation. No sooner do I take a title from the shelf, blow off the dust, and wipe down the cover than I find myself sitting on the floor with legs crossed and my back against the wall. Pretty soon books get piled up on my legs as I am reunited with old friends.
It is as if these books have voices, and each wants to say its piece. “Remember me? I was given to you when you went into the Navy, so that you would never lack for companionship,” one whispers. Another says, “I was your first book of poems, given to you before you learned to love poetry.” And a third, “I was the book that made history so attractive to you.”
Perhaps the greatest pleasure of re-organizing my books are the surprises — or better said, reunions — that occur. During my latest book-cleaning adventure, I found one that had fallen behind the shelf: “Tales of Edgar Allan Poe.” Not an unusual title, but the words written on the first page made it very special: “With Love from Mom and Dad, Christmas 1965.” What’s this? A book on the physics of lasers（激光）. It is filled with mathematical statements, and I had bought it at a library sale when I was 12, not long after the laser had been invented. I couldn’t understand a bit of it, but I did learn what “laser” meant.
What I end up with when I empty my bookshelves is a cross-section (横剖面) of my personal history. It’s like a road cut where one sees all the layers of rock going back through time to the beginning of the simplest life forms. The books I’ve read — and kept — are not just old friends. They are my résumé.
50. What could be said about the author?
A. He is too busy to tidy up his bookshelves.
B. He considers his books treasured possessions.
C. He has made a lot of notes in his books.
D. He is a lover of science books.
51. By saying that his books have voices, the author means ________ .
A. they bring back happy memories
B. they are recorded in human voice
C. they say a lot about human history
D. they offer good topics for discussion
52. What does the author enjoy most from re-organizing his books?
A. Finding some missing books.
B. Putting books in good order.
C. Learning something new from the books.
D. Rediscovering interesting stories behind some books.
53. The underlined word “résumé” in the last paragraph probably means ______.
A. personal history B. precious notes
C. good companion D. simple life forms
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，则f′(x)＞0，f(x)递增，
和
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和
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