Christchurch Writers' Guild

The Misunderstood Semi-Colon

Posted on August 18, 2013 Updated on August 18, 2013

The semi-colon stakes a claim as the most misunderstood punctuation mark in the English language.  That’s probably because it is the one that people see the least.  And when they do see it, it’s often not being used correctly.

What to know about the semi-colon:

1. It looks like a comma and so is often mistakenly used to fill in for one.  Part of the problem is that semi-colons can actually be used to fill in for commas – but only in a list.

2. The rest of the time, semi-colons are more closely related to colons:  ‘semi’ apparently comes from the Latin term ‘half’, and means ‘partially’, ‘somewhat’, or ‘having some of the characteristics of’ whatever it is referring to.  So the semi-colon is a little bit like a colon.  Keep this in mind and you might have some luck with it – if you’re not writing a list, a semi-colon cannot be used an alternative to a comma.

The semi-colon is rare because there are only two circumstances in which it should be used:

1. When you are joining two independent sentences.

The semi-colon is not like a comma because commas are never used for joining independent sentences.  If they are, what is created is called a ‘run-on sentence’ or ‘comma splice’.

Independent sentences (clauses that make sense by themselves and contain a subject and verb) should be separated with a full-stop or joined with a conjunction.  However, sometimes you can join them with a semi-colon instead of a full-stop.  The time to do that is when the sentences are linked by their content in some close way.  This is how the semi-colon acts as a sort of colon – if the first sentence was followed by a colon, the second sentence would explain the first in some way.  With a semi-colon between them, two sentences are also closely linked contextually, but not at that specific explanatory level.

Here are some examples:

• I walk to the park every Sunday morning; the gates open at ten.
• She looked at me as though I was a monster; I felt my stomach sink.

The test for using a semi-colon in sentence structure is – could you replace it with a full-stop?  If the answer is yes, then it is ok to use it.  If the answer is no, then please don’t use it!

2. When you are listing something

I think most people know that when you are about to list a whole bunch of stuff, you signal that with a colon.  Normally, things in a list are separated by commas.  But, sometimes, it is appropriate to use semi-colons instead.  This is the only time when a semi-colon can stand in for a comma.  And it is only used this way when the items in the list could become confused (or confusing) due to the use of commas for additional phrases.  For example:

• She gave me her shopping list: apples, pears, bread, milk, chocolate, and biscuits. [commas are fine; a semi-colon isn’t needed!]
• She gave me her shopping list: apples to give to Joseph and make pies for Saturday; pears for Aunty Flo and the baking contest; bread for sandwiches for the picnic; milk, even though she knows Toby can’t drink it and Stephanie doesn’t like it; chocolate for me, because she knows I can’t live without it, although she’s been trying to get me to stop eating it for several weeks; and biscuits, which we have to stock up on, because when Nana visits she goes ballistic if she can’t have something to dunk in her tea. [without the semi-colons to separate list items, the reader could easily become confused]

Feeling more confident about semi-colons now?  Want a second opinion about some sentences you have in mind?  Don’t hesitate to post here for some help!