约220字。
　　Unit 2 《The United Kingdom》教案
　　Part Two: Teaching Resources (第二部分：教学资源)
　　Section 1: A text structure analysis of PUZZLES IN GEOGRAPHY
　　I. Type of writing and summary of the ideas
　　Type of writing This is a piece of expository writing. 说明文
　　Main idea of the passage
　　It tells us about the puzzles in the historical geography of London.
　　Central idea of 1st paragraph Why are different words used to describe England, Wales, Scotland and Northern Ireland?
　　Central idea of 2nd paragraph First there was England.
　　Central idea of 3rd paragraph Great Britain was the name given when England and Wales were joined to Scotland.
　　Central idea of 4th paragraph The four countries are still very different.