Notice how many times Fitzgerald uses the words hope, or dream. Why does he do this?

The American Dream is one of the main themes of the story. Hopes and dreams are what fuel people to achieve a piece of that dream. The American Dream means different things to different characters. Gatsby represents this dream in a big way. Everything about his outward appearances is big except for the man himself. Gatsby is a self-made man which reinforces the possibility, although remote, for anyone to achieve the dream. Thus these words hope and dream resonate throughout the novel.