单项选择题The college with the longest history in America is ______.
单项选择题All of the following words except ______ belong to the closed class.
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 ______.