Page 326
Colon
A colon is used in three special cases, including to show time.
To make a colon, put one dot on top of another one (:).
Between Numbers in Time
Use a colon between the parts of a number showing time.
I woke up at 6:45 a.m.
Tonight, I’ll go to bed at 9:30 p.m.
In a Business Letter
Use a colon after the greeting in a business letter.
Dear Mr. Frank:
Dear Editor:
Dear Ms. Grohl: