PeriodsDO use periods:
At the end of a sentence
- Researchers found no correlation between types of therapy used and recidivism.
At the end of an indirect question (that is, a report about the question rather than the question itself)
- I next asked how long she had maintained sobriety.
NOTE: A direct question ( How long have you maintained sobriety? ) would end with a question mark.
After most abbreviations
- Please see Dr. Li when you get a chance.
After the two-letter postal abbreviation of states (PA, NY, NJ).
After groups of initials (FBI, CIA, AIDS)
If the last word of the sentence already ends with a period. (You would never use two periods at the end of sentence.)
The meeting will start at 5:30 p.m.
Special Tip: If you are quoting, the period normally goes inside quotation marks.
Example: Then he said, "I hope this is the last time we will have to meet here."
However, when you are following APA guidelines, and the quote is followed by a parenthetical reference like the examples below, you must first finish the quote, then the reference, and then put the period at the very end.
As Sanchez and Marks point out, "Addiction rates among inner city teenagers are rising at an alarming rate" (2004, p. 35).
"Addiction rates among inner city teenagers are rising at an alarming rate" (Sanchez & Marks, 2004, p. 35).