the book which was witten by LuXun sold well yesterday.（改为简单

（witten） 是过去分词作定语修饰Harry Potter ,
相当于定从:...Harry Potter （who was written） by JK Rowling.

Wild Grass or Yecao was Lu Xun's collection of prose poems. It was published in 1926 and included 23 prose poems (one actually in play format) written in 1924 and 1926. The title he gave to the collection is Wild Grass. In his prelude to the collection he wrote:
At the moment of light vs. dark, life vs. death and past vs. future, I provide this patch of wild grass as evidence for all, friends and enemies, humans and beasts, the loved and the unloved.

easons(人们对美国年轻人有这么大兴趣是有原因的）
half（占据一半人口）
college（这些年轻人中很快就要进入美国的大学,与后面的College students today have strange opinions 和上文中Today there are about seven million Americans in colleges and universities.相照应）
understand（对于年纪大些的人来说,理解他们的想法和感觉是有必要的）
strange（新奇的观点）
making（让更多的人过上美好生活）
fair（特别是对于那些没有被给予公平机会的人）
way（对于他们来说,用旧方法看待什么是对的,什么是好的很困难）
Millions of words have witten about young people in the United States.There are reasons for this great interest in the ideas,feelings,and actions of youth.
Today there are about seven million Americans in colleges and universities.Young persons under twenty-five make up nearly half of the American population.Many of these will soon be in college of the nation.Naturally their ideas are important to everyone in the country,and it is necessary for older people to understand what they think and feel.
College students today have strange opinions about right and wrong.They are deeply interested in making a better life for all people,especially for those who have not been given a fair chance.They think much is wrong in the lives of their parents.It is hard for them to see what is right and good in the older way.As a result,there is often a lot of trouble in American families.

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