题目内容：
The twentieth century saw great change. In your opinion, what is one change that should be remembered about the twentieth century? Write an essay of about 400 words to state your opinion.In the first part of your essay you should state clearly your main argument, and in the second part you should support your argument with appropriate details. In the last part you should bring what you have written to a natural conclusion or make a summary.
Marks will be awarded for content, organization, language and appropriateness. Failure to follow the above instructions may result in a loss of marks.
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