概括：内容选自老托福听力，是练习托福听力的绝佳材料。


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North American
In today's class we'll be examining some 19th century pattern books that were used for building houses. I think it's fair to say that these pattern books were the most important influence on the design of North American houses during the 19th century. This was because most people who wanted to build a house couldn't afford to hire an architect. Instead, they bought a pattern book, picked out a plan, and took it to the builder. The difference in cost was substantial . In 1870, for example, hiring an architect would've cost about $100. At the same time, a pattern book written by an architect cost only $5. At that price, it's easy to see why pattern books were so popular. Some are back in print again today, and of course, they cost a lot more than they did 100 years ago. But they're an invaluable resource for historians, and also for people who restore old houses. I have a modern reprint here that I'll be passing around the room in a moment, so that everyone can have a look.