The semicolon is frequently misused, probably because it is not the most commonly used mark of punctuation.
Perhaps, because of its name, it may be confused with the colon.
This mark of punctuation indicates a "pause” that is part way between the comma and the period.
Look at a comparison of three common marks of punctuation.
(a) Two short sentences – ending with the period.
John is driving to the concert. Genevieve is travelling by bus.
The ideas or thoughts above are related, so they can be placed into a single sentence. To do that, you must add a conjunction and place a comma before the conjunction.
(b) The comma is used between two sentences if the conjunction is used.
John is driving to the concert, but Genevieve is travelling by bus.
You can also join the two sentences but without a conjunction. In that case, as below, you need the semicolon.
(c) This important mark of punctuation (;) is used to join two sentences when there is no conjunction.
John is driving to the concert; Genevieve is travelling by bus.
In the above three examples, you can see how each mark of punctuation is used and compare the three.
THE COMMA SPLICE
If you switch to the comma in the following sentence, you have a rather common error:
John is driving to the concert, Genevieve is travelling by bus.
It’s called a comma splice or a run-on sentence. You need more than a comma to join two sentences.
Punctuation is important to provide the proper meaning for English writing. Without punctuation, meanings can easily become misunderstood. Your goal is to write clearly.
Now that you know the difference, you can avoid the error and you can write correctly.
TEST YOUR UNDERSTANDING
Here are some quiz sentences to check your basic understanding.
(1) Correct or Incorrect?
Thanks for taking the time to visit yesterday.
(2) Correct or Incorrect?
Sally has received her graduation diploma; and she is very excited to be moving forward.
(3) Correct or Incorrect?
George and Jim are brothers; they were born two years apart.
(4) Correct or Incorrect?
George and Jim are brothers, they were born two years apart.
(5) Correct or Incorrect?
George and Jim are brothers, and they were born two years apart.
If you guessed that #3 and #5 are correct, congratulations!
(1) Should be a colon
(2) Should be a comma
(4) This is a comma splice. Change the comma for the semicolon.
Onward and upward!