The following definitions and examples are
from ChompChomp.com.
Grammar Bytes!
Grammar Instruction with Attitude
©1997 - 2007 by Robin L. Simmons
All Rights Reserved.
The first appropriate use of the semicolon is
to connect two related sentences. The
pattern looks like this:
Complete sentence + ; + complete
sentence .
Here is an example: My eighty-one-year-old
grandmother still rides her Harley
motorcycle; her toy poodle balances in a
basket between the handlebars.



You can also team up a semicolon with a
transition to connect two complete sentences
that are close in meaning. The pattern looks
like this: Complete sentence + ;
+ transition + , + complete sentence .
Check out this example: My father does not
approve of his mother cruising around town
on a Harley motorcycle; however, Grandma
has never cared what anyone thinks.

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Finally, use the semicolon to avoid confusion
when you have complicated lists of items. The
pattern looks like this: Item + , + More
Information + ; + Item + , + More
Information + ; + and + Item + , + More
Information
Read the following example: On a Harley
motorcycle, my grandmother and her poodle
have traveled to Anchorage, Alaska; San
Francisco, California; and Tijuana, Mexico.
Keep these three things in mind when you use a
semicolon:
 The two main clauses that the semicolon joins
should be closely related in meaning.
 Don't capitalize the word that follows the
semicolon unless that word is a proper noun, one
that is always capitalized.
 Limit your use of semicolons; you should not
scatter them wantonly throughout your writing.
Semicolons are like glasses of champagne; save
them for special occasions.
Thanks to OWL,
the Online Writing Lab from Purdue University,
for the following information.
after a complete statement in order to introduce
one or more directly related ideas, such as a
series of directions, a list, or a quotation or other
comment illustrating or explaining the
statement. For Example:

The strategies of corporatist industrial unionism
have proven ineffective: compromises and
concessions have left labor in a weakened
position in the new "flexible" economy.

The daily newspaper contains four sections:
news, sports, entertainment, and classified
ads.

He said he would be at home by 5:30 p.m.

He always liked to refer to Genesis 1:18 when
starting a speech.
Space once between a colon and the next word,
when the colon is used between words. Do
not space between numerals and a colon
when a colon is used to mark time or ratios.