10 Uses for the Period

“...punctuation marks are the traffic signals of language: they tell us to slow down, notice this, take a detour, and stop.” 
― Lynne Truss "Eats Shoots Leaves"

One of my goals for the class this semester has been to make them "Masters of the Comma."  That elusive little bit of punctuation causes the most trouble in their writing.  Contrary to popular opinion, you don't just throw one in every time you would pause or take a breath.  We have some pretty clear guidelines about its usage that also involves knowing more about other grammar topics.

The period, on the other hand, is much more straightforward.  Below are the 10 uses for the period.  And, yes, there will be a test on these.

1.  Place a period at the end of a declarative sentence, at the end of an indirect questions, and at the end of an imperative sentence that does not express strong emotion.

2.  Place a period after a request.  A question mark is not used.

        Ex.  May I have your opinion on the subject.

3.  Place a period after an abbreviation that stands for a single word.

     Ex.  John Jones and Co.          Mrs. Jameson

            Jan. 6                               Wireless, Inc.

     Note:  The trend is to eliminate periods in abbreviations, especially in measurements:

          lb or lb.          hr or hr.          oz or oz.          mph or m.p.h.          yd or yd.

     Note:  When the last word in a sentence is abbreviated, one period will suffice.

          Ex.  We plan to meet at 9 a.m.

     Note:  Before a colon or semicolon, the period for an abbreviation is omitted.

          Ex.  The instructions came from Fox Bros. Ltd:  Never use the materials without the proper equipment.

                 

4.  Periods are used after initials representing full names. (ex.  John Q. Smith) For some famous names, the periods may be omitted. (ex.  FDR, JFK)  In monograms periods are always omitted.

5.  Place periods after letters or figures in an outline when they mark the chief division of a subject.  Omit the periods when the letters or figures are in parentheses.  Periods are also used when making lists with either numbers or letters.

     Ex.  I.

              A.

                  1.

                     a.

                        (1)

                            (a)

6.  Place a period before a decimal.

     Ex.  $20.58          .05          12.6           .8398798

7.  A period may be used in place of the colon when denoting hours and minutes or in dates

     Ex.  10.15 for 10:15          4.03.13 for 4-3-13 or 4/3/13

8.  Place a period inside the parentheses when they enclose an independent sentence.

     Ex.  The firm was founded a few years ago.  (I am not sure about the exact date.)

9.  Use three periods separated by spaces to denote an omission in quoted matter.  When the omission occurs at the end of a sentence, the sentence period is retained as well.  Use seven periods spaced across the page to denote the omission of one or more paragraphs of quoted material.

     Ex.  Henry Clay declared that the proposal was agreeable . . . if respectable and efficient.

10.  Periods are used in web addresses and e-mails.

     Ex.  myname@funmail.com          www.google.com