题目内容

A.To demonstrate the importance of public health laws.B.To point out that without luck

A. To demonstrate the importance of public health laws.
B. To point out that without luck businesses will not succeed.
C. To explain how traveling led to new inventions.
D. To illustrate the importance of having the right product at the right time.

查看答案
更多问题

A.He also plans to drop a class,B.He also waited in line for a long time today.C.He do

A. He also plans to drop a class,
B. He also waited in line for a long time today.
C. He doesn't know where to go to drop a class.
D. He missed the deadline for dropping a class.

A.To correct a common misunderstanding about grasshoppers.B.To help explain how well g

A. To correct a common misunderstanding about grasshoppers.
B. To help explain how well grasshoppers can jump.
C. To compare the size of grasshopper with that of other insects.
D. To show how quickly grasshoppers respond to danger.

听力原文:Excuse me, I've been using this old book for a research project and I noticed that a lot of pages are turning brown and becoming brittle.
Yes, unfortunately, that's a common problem with books made from wood pulp.
I suppose to make paper from wood that you have to add a lot of chemicals and acids to make it turn white.
Exactly and it's the acid that eventually eats away the paper.
Oh, that actually make sense, but this book's not even 75 years old and I've seen books in museum that are hundreds of years old and they're in fine condition.
Well, you see, books have been made from wood pulp only since 1850's, before that they were made from materials mostly animals' skins or C, no chemicals were added.
It's a shame those older wood pulp books are going to fall apart some day. Is there anything that can be done to preserve them.
En, currently the only way to stop the books from decaying is to remove the binding and treat each page individually to remove the acid.
That doesn't sound very economical.
No, it isn't. It's not practical to treat a large number of books with this process, so we only try to rescue the most valuable 1st edition books in our collection.
Well, thanks for the explanation. I'd better get back to my project.
Good luck, and I hope the old book hold long enough for you to finish it.
(31)

A. The early history of bookbinding.
B. How old books become valuable.
C. Economical ways to protect old books,
D. Why some books deteriorate.

A.She needs to relax.B.The man should try harder to concentrate.C.She has almost finis

A. She needs to relax.
B. The man should try harder to concentrate.
C. She has almost finished the reading assignment.
D. The music will bother her.

答案查题题库