Six geographical regions of the United States:
New England: Connecticut, Massachusetts, Maine, New Hampshire, Rhode Island and Vermont.
Central region: Washington, D.C. (DC), Delaware (Delaware), Maryland (Maryland), New Jersey (New Jersey), New York (New York) and Philadelphia (Pennsylvania).
Midwest: Iowa, Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, North Dakota, Nebraska, Ohio, South Dakota and so on.
Western regions: California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, Washington and Wyoming.
Southern regions: Alabama (Al), Arkansas (AR), Florida (FL), Georgia (GA), Kentucky (ky), Louisiana (LA), Mississippi (MS), North Carolina (NC), South Carolina (SC), Tennessee (TN), Virginia (VA) and West Virginia.
Southwest China: Arizona (AZ), New Mexico (NM), Oklahoma (OK) and Texas (TX).