Gatsby tells Nick that he is from the Midwest, and that he has an extensive background in farming. This means that Gatsby was raised on a farm in the midwest, and that he understands how to farm and raise crops.
Gatsby tells Nick that he attended college at Oxford University in England. This means that Gatsby attended one of the most prestigious universities in all of Europe, Oxford University, where he studied economics and business management.
Gatsby tells Nick that he served in the military during World War I. This means that Gatsby served in the Army during World War I, which took place between 1914-1918. The countries involved in this war were Germany (who lost), France (who won), Russia (who also won), Great Britain (which won), Italy (which lost), Japan (which lost).
Gatsby tells Nick that he is currently employed as a stockbroker. This means that Gatsby works as a stockbroker for an investment firm or company which invests money into companies and organisations to make them grow larger and more successful financially over time so they can sell shares of their company publicly on Wall Street or elsewhere so people can buy them with cash money if they want too buy them off.
