Periods, Questions marks and Exclamation points
Use a period at the end of a statement. This English class is my favorite class this term. Use a period at the end of a command. Hand in the essays no later than noon on Friday. Use a period at the end of an indirect question. The teacher asked why Maria had left out the easy exercises. Use a period with abbreviations: Dr. Espinoza arrived from Washington, D.C., at 6 p.m.
Although it is tempting, we DO NOT use periods in acronyms. An acronym is an abbreviation that we pronounce as a word instead of as individual letters. SCUBA (self contained underwater breathing apparatus) NATO (North Atlantic Treaty Organization)
Abbreviations we pronounce by spelling out the letters may or may not use periods. If you are unsure in that specific case, look up the abbreviation in a dictionary. FBI (Federal Bureau of Investigation) Notice we say “F-B-I” but there are no periods U.S.A. (United States of America) Notice we say “U-S-A” but there are periods LSHS (Lake Shore High School) Notice we say “L-S-H-S” but there are no periods
Use a question mark at the end of a direction question. He should quit smoking, shouldn't he? If a question mark is part of an italicized or underlined title, make sure that the question mark is also italicized: My favorite book is Where Did He Go? When a question ends with an abbreviation, end the abbreviation with a period and then add the question mark. Didn't he use to live in Washington, D.C.?
When a question constitutes a polite request, it is usually not followed by a question mark. Would everyone in the room who hasn't received an ID please move to the front of the line.
Use an exclamation point at the end of an interjection Wow! Use an exclamation point at the end of a strong command Sit down! If an exclamation mark is part of an italicized or underlined title, make sure that the exclamation mark is also italicized or underlined: My favorite book is Oh, the Places You'll Go!