What may be Nick's motives for telling the story? - Nick wants to show Gatsby's personality and life to the rest of the world. - He's trying to bust the great myth that wealth gives happiness.

Why did he choose a 1st person narrator? - It becomes more subjective. He can tell the story from a different point of view. - The characters, Gatsby in particular, remains mysterious, since Nick doesn't have access to their thoughts.

How does it affect our reading? - Because the story is written from Nick's point of view, you share his views and his feelings.

Gatsby asks Nick about the bond business and says he can get him a great job.

" 'Well, this would interest you. It wouldn't take up much of your time and you might pick up a nice bit of money. It happens to be a rather confidential sort of thing.'
I realise now that under different circumstances that conversation might have been one of the crisis of my life. But, because the offer was obviously and tactlessly for a service to be rented, I had no choice except to cut him off there." (p 53, l 16).

Nick has to solve the truth simultaneously with the reader:

Nick drives with Gatsby to town and Gatsby tells him about his life.

"He looked at me sideways - and I knew why Jordan Baker had believed he was lying. He hurried the phrase 'educated at Oxford', or swallowed it, or choked on it, as though it had bothered him before. And with this doubt his whole statement fell to pieces, and i wondered if there wasn't something a little sinister about him, after all." (p 42, l 14).

Reliable? He is a nice guy. Nick's goals aren't depending on other people's failings.

Why 1st person? Nick has to go through the same process as the reader to solve the truth. Therefor the truth conceals as long as possible. If the narrator was 3th person, it would be harder to hide the truth.