题目内容
What is the lecture mainly about？
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SECTION A CONVERSATIONS
Directions: In this section you will hear several conversations. Listen to the conversations carefully and then answer the questions that follow.
听力原文：W: 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.
M: Yes, unfortunately, that's a common problem with books made from wood pulp.
W: I suppose to make paper from wood that you have to add a lot of chemicals and acids to make it turn white.
M: Exactly, and it's the acid that eventually eats away the paper.
W: 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.
M: Well, you see, books have been made from wood pulp only since 1850, before that they were made from materials mostly animals' skins or C, no chemicals were added.
W: 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.
M: 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.
W: That doesn't sound very economical.
M: 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 first edition books in our collection.
W: Well, thanks for the explanation. I'd better get back to my project.
M: Good luck, and I hope the old book hold long enough for you to finish it.
According to the man, why do modern books decay？
Why don't the speakers have any food to eat？
A．建立该查询处理程序所用到表的视图，并对程序作相应的修改B．将该查询处理程序所用到表进行
听力原文：W: Did you know it was going to rain today？
M: Absolutely not, this comes as a total shock at me, especially since the paper said mostly sunny.
W: Well, I guess the paper must've meant "mostly sunny somewhere else". But since we've come all this way, why don't we just move the blanket under that tree.
M: That's a good idea. It looks like it's still dry there, so, as long as it doesn't start to come down any harder.
W: You didn't happen to bring a spare blanket, did you？ Because this one is all wet now.
M: No. But I do have some folding stools in the car. Will they do？
W: They will be just fine. I'm really hungry, so while you are there, how about bringing out the food？
M: I thought you were bringing the food.
W: This is unbelievable! If I weren't so hungry, this would be really funny. So what now？
M: What's the name of that restaurant you like so much again？
What are the speakers trying to do？
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