Read the excerpt from Travels with Charley.
For many years I have traveled in many parts of the world. In America I live in New York, or dip into Chicago or San Francisco. But New York is no more America than Paris is France or London is England. Thus I discovered that I did not know my own country. I, an American writer, writing about America, was working from memory, and the memory is at best a faulty, warpy reservoir. I had not heard the speech of America, smelled the grass and trees and sewage, seen its hills and water, its color and quality of light. I knew the changes only from books and newspapers. But more than this, I had not felt the country for twenty-five years.
The author most frequently uses _____
to support his purpose of informing the reader of his past.