One of the easiest mistakes to make writing in English is to use run-on sentences. These are common grammatical errors where the writer smashes two or more complete sentences without appropriate conjunctions or punctuation. Now, grammatical errors are something you want to avoid in work you plan to publish, but there’s an even more important problem with run-on sentences: they’re just plain hard to read.
Imagine you have a lot of important technical information to relay, and it’s all connected. How can you make sure your reader understands everything and doesn’t get lost? Luckily, English places a multitude of tools at your disposal to place strategic breaks in your writing. This is punctuation, and using the right symbols in the right places provides a roadmap for breaking down even highly complicated sentences into understandable chunks.
Three of the most common (and thus commonly misused) punctuation marks for this are commas, colons, and semicolons. There are important differences – both major and subtle – between these symbols and here I’ll be explaining the difference in usage, and why it matters.
Commas
Commas are by far the most versatile of the ‘breaks’ you can use. They are put in pretty much whenever you need to provide breathing room between ideas or events to prevent confusion. In many cases, you can simply imagine speaking the words of your text out loud. Wherever you naturally pause, you can probably put a comma. Of course, comma use isn’t purely intuitive. There are also set rules for when and when not to use commas. This gives consistency for both you and your reader.
Here are the times when you should use commas:
1. When you are separating independent clauses, and connecting them with a conjunction such as and, but, for, or, nor, so, or yet.
2. When separating an introductory clause, phrase, or word from the main clause. If you have an introductory clause, it will likely start with after, although, as, because, if, since, when, or while. Introductory phrases will commonly begin the past participle. Introductory words… well, it really can be whatever makes sense describing the main clause.
3. When including information that is relevant, but not necessary to one’s comprehension of the sentence. These clauses, referenced by me in previous posts, are called dependent clauses, and can be inserted with commas pretty much anywhere in a sentence the author chooses.
4. When naming three or more words or phrases in a series.
5. When writing geographical names, divisions in dates (except month and day), addresses (except street number and name), and people’s titles.
6. When shifting between a quotation and a description of or commentary on the quote.
Colons
Thankfully, colons are much impeller than commas. Their primary purpose is to introduce or direct attention to a list, a quotation, or an example/explanation. Unlike with commas, the introduction before a colon must be an independent clause. I often see lists with a colon where something like “including: a, b, and c” is used. While this likely will not be noticed, it is technically incorrect grammar, and the colon should simply be removed as it is unnecessary.
The introduction of a quote or an explanation tends to invite this problem less, but it’s still important to remain vigilant. When starting with a dependent clause, a sort of call-and-response is established in the writing. The first half is grammatically complete, but informationally incomplete; The second half provides the relevant details. Essentially, a colon should never be used somewhere; their absence would not affect the sentence. If you feel you need to add breathing room in a sentence use a comma.
Other uses for colons include the following: separating numbers in times or bible verses, separating information in citations, indicating a subtitle following a title, and after the salutation in a formal memo.
But whether the colon precedes a list, a quote, or an explanation, the following word it’s important to remember that the following word is not capitalized (unless it is a proper noun).
Semicolons
I have often resisted using semicolons in my writing for a couple of reasons: The first is I wasn’t entirely sure how to use them. The second was that because I wasn’t sure how to use them, I didn’t know how others would read my sentences that used them. Fortunately, semicolons are fairly simple to explain.
Semicolons are essentially just what they look like, which is a period stacked on top of a comma. They join two independent clauses where typically a conjunction such as ‘and’ would be used. This serves the purpose of indicating a continuity between two ideas without forcing the reader to navigate a bloated, difficult sentence. It also represents a greater pause than a comma, emphasizing both the independence of the ideas and their connection.
The other common use of a semicolon is when dividing items in a serial list. This means a list that is either long or contains internal punctuation.
To learn more about the proper use of grammar, and how it affects the meaning and flow of your written work, contact me.