单项选择题Henry David Thoreau was the author of the world-famous ______.
单项选择题Which of the following words does not belong to the open class
单项选择题The term The 'Lost Generation mainly refers to the American generation of young people after ______.
单项选择题Which of the following is an endocentric construction
单项选择题White people account for about ______ of the total population of America.
