Addresses
Use the abbreviation Ave., Blvd. and St. only with a numbered address:
1600 Pennsylvania Ave.
Spell them out and capitalize when part of a formal street without a number:
Pennsylvania Avenue.
Lowercase and spell out when used alone or with more than one street name:
Massachusetts and Pennsylvania avenues.
All similar words (alley, drive, road, terrace, etc.) always are spelled out. Capitalize them when part of a formal name without a number; lowercase when used alone or with two or more names.
Always use figures for an address number:
9 Morningside Circle.
Spell out and capitalize First through Ninth when used as street names; use figures for 10th and above:
7 Fifth Ave., 100 21st St.
Use periods in the abbreviation P.O. for P.O. Box numbers.
Cities/states
Capitalize city if part of a proper name, an integral part of an official name or a regularly used nickname:
New York City, Kansas City, Windy City, City of Light.
Lowercase elsewhere:
a Texas city, the city government, the city Board of Education; and all other city of phrases: the city of Lexington.
Capitalize when part of a formal title before a name:
City Manager Lynn Smithson.
Lowercase when not part of a formal title:
city Health Commissioner Frank Smith
Use a comma after the city and after the state:
She was born in Lexington, Kentucky, in 1985.