Answer: Gatsby built his mansion to recapture his past.
Explanation: ‘Can’t repeat that past?’ he cried incredulously. ‘Why of course you can!'
This is significant because Gatsby wanted to re-live the past. He wanted to re-shape what has already taken place and somehow will his future with Daisy to happen. Gatsby attempts to void the the five years they had not seen each other. He ignores the fact that Daisy is married to Tom and has a child with him.