Always use a comma between the name of a city and the name of a state, like this:
Chicago, Illinois
My mother was born in Chicago, Illinois.
Also use a comma between the name of a city and a country, like this:
Munich, Germany
My neighbor is a native of Munich, Germany.
If the city and state or city and country is not written as the last words of the sentence, we must put a comma after the state or the country also, like this:
My neighbor visited Munich, Germany, last summer.
Janet is traveling to Denver, Colorado, in September.
Always place a comma between a city and state and between a city and country. Also place a comma after the state or country if that isn’t the end of the sentence.
▶It’s your turn. Place a comma or commas where they belong in this sentence. My friend is studying in Vienna Austria next fall. Did you place two commas in this sentence? Good for you!