Using Commas, Semicolons, and Colons Within Sentences

Punctuation within sentences can be tricky; however, if you know just a few of the following rules, you will be well on your way to becoming a polished writer and proofreader.

Rule: Use a comma between two long independent clauses when conjunctions such as and, or, but, for, nor connect them.
Example: I have painted the entire house, but she is still working on sanding the floors.

Rule: If the clauses are both short, you may omit the comma.
Example: I painted and he sanded.

Rule: If you have only one clause (one subject and verb pair), you won’t usually need a comma in front of the conjunction.
Example: I have painted the house but still need to sand the floors.
This sentence has two verbs but only one subject, so it has only one clause.

Rule: Use the semicolon if you have two independent clauses connected without a conjunction.
Example: I have painted the house; I still need to sand the floors.

Rule: Also use the semicolon when you already have commas within a sentence for smaller separations, and you need the semicolon to show bigger separations.
Example: We had a reunion with family from Salt Lake City, Utah; Los Angeles, California; and Albany, New York.

Rule: A colon is used to introduce a second sentence that clarifies the first sentence.
Example: We have set this restriction: do your homework before watching television.
Notice that the first word of the second sentence is not capitalized. Whether to capitalize the first word after a colon depends on the stylebook or style guidelines you are following. If you have multiple sentences following the sentence with the colon and you bullet or otherwise itemize them, capitalization and punctuation are optional. For example, if each bullet or numbered point is a complete sentence, you might capitalize the first word and end each sentence with proper ending punctuation. The rule of thumb is to be consistent.

Rule: Use a colon to introduce a list when no introductory words like namely, for instance, i.e., e.g. precede the list.
Example: I need four paint colors: blue, gray, green, and red.

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253 responses to “Using Commas, Semicolons, and Colons Within Sentences”

Is there a “golden rule” for spacing AFTER a period and before the next sentence? I’ve been arguing with someone for quite some time that it is one — NOT 2 — spaces after each period. Please help us settle our quarrel!

Our Rule 1 of Spacing with Punctuation states, “With a computer, use only one space following periods, commas, semicolons, colons, exclamation points, question marks, and quotation marks. The space needed after these punctuation marks is proportioned automatically.”
Originally, typewriters had monospaced fonts (skinny letters and fat letters took up the same amount of space), so two spaces after ending punctuation marks such as the period were used to make the text more legible. However, most computer fonts present no difficulty with proportion or legibility, so use just one space after a period, colon, question mark, or exclamation point at the end of a sentence.

the story of spaces at the end of sentences may be more complicated than the traditional lore because in the years of professional printing before the typewriter, typesetters tended to use wide spaces at the end of sentences whether their fonts were monospaced or proportional. Yet, it is true that during the era of the typewriter, two spaces ruled, and once computers became the dominant tool for typing, one space became the standard.

Can’t believe I’ve never heard the one space rule? I recenlty completed another degree, which required writing many papers and always used the 2 spaces. Not once did I get called out on it.

I am 35 and I have always used 2 spaces after a period. I didn’t even realize it was a thing (outside APA format papers) to only do one space. It is going to be a real hard habit to break. It’s just what my fingers do.

That is how it was explained to me. It originated with typesetters during the manual printing press days. It carried over to non-proportional type in early typewriters for the same reason you gave. Nowadays, with proportional true type fonts, it is no longer necessary and has become an anachronism. Single space after a period is now the accepted practice.

Being a dinosaur that I am…the rule I was taught was two spaces after a period. When I made the switch from typewriting to word processing I noticed one problem with using two spaces after a period. When you “justify” the margins on sentences that use two spaces, then more spaces would be added in automatically (by the software program) if I did not switch to one space after the period. As long as I was not justifying margins I could continue to use two spaces. Just an observation from a writer with thirty years of following the rules.

Standard practice for spacing after a sentence is two spaces but most students today use only one. It is frustrating because the text flows better with two spaces as it makes the reader pause slightly before the next sentence when there is a clearer break. Grammar in general often goes through trends like fashion and can be different based on cultures and regions. However, this is a fairly new stylistic trend and is most likely one born from laziness and new technology which are factors related to many changes in the way we do things! I guess this 51-year-old educator has to buck up and deal!

I have ordered your book. Thank goodness for you! You make the arcane clear, and have lifted the fog that impeded my way in Grammarland. Thank you

I notice people using just once space between sentences now, but we were taught that it is correct to use two. Has the rule changed?

Yes, the rule has changed or at least is changing so rapidly that I would suggest using only one space after the ending punctuation mark.

e.g. is an abbreviation from the Latin “exempli gratia,” which translates to “for example”
Example: You will need some baking ingredients; e.g., butter and sugar.

Rule: Use a comma between two complete, long clauses (two subject and verb pairs) when conjunctions such as and, or, but, for, nor connect them. When I studied grammar (punctuation was part of grammar) in the early fifties in Australia, conjunctions (also referred to in Australia as joining words) and which also include “also” and “too” but not “for” had two rules :
1) They could never start a sentence; and
2) They could never have a comma in front of them (whether clauses were long or not).
If one was using a comma to denote a breathing space it always came after the conjunction. I don’t know whether this is a difference between countries but Australia has traditionally used English as distinct from American English and up until about fifteen or so years ago there was no confusion but I notice this is changing rapidly here now as Australia becomes more and more Americanised. (Yes, “ised” not “ized”). I guess we’ll have to wait and see what develops. I don’t know what is currently being taught in schools. As for spaces after a full stop (American = period), the printing industry has always used two as a standard. I suspect this is rapidly changing as the use of HTML for web pages only allows a standard one space. A non-breaking space has to be used to insert a second one and I suspect for most coders this is not worth the effort even if they are aware of the printers’ standard. I only found this site by accident but it is real interesting. Keep up the good work. Viva la difference!

Johno, if in Australia you cannot start a sentence with a conjunction and do not use commas in front of them ever, the rules there are different from American grammar and punctuation rules. “Viva la difference” is a good attitude to have!

Could you clear up whether or not to put a comma in this example after ‘are’? Research shows that teens are, “more likely to drop out if they do drugs.”

In Australia I wouldn’t put a comma here. It’s not direct speech and flows naturally, without the comma, as a quote.

do I have the commas in the correct space? I have two clients, Ed and Pat, whom I have worked with for several years…

I was wondering whether it’s strictly wrong to have a conjunction after a comma in British English. I find that sometimes when sentences are very long it feels natural to have a coma before the word “and”. I am Swedish- can it be that Swedish punctuation rules differ from English ones? As far as I can remember there are occasions when it is correct to use a comam before conjunctions.

In the U.S., it is preferred to use a comma before “and” in a series of three or more. However, in order to save precious space, newspapers do not use this comma. I believe that the preferred method in British English is to leave out the comma but I don’t believe it is considered wrong to put the comma in.

I had a question regarding the issue of one or two spaces following a colon that is followed by an independent clause. When you say that if the colon is followed by merely one complete sentence, that second clause should not be capitalized, but if it is followed by two or more, that same clause should be capitalized, do you mean “two or more” sentences in the same paragraph? Or two or more sentences that are closely related to the idea followed by the colon? Because I imagine most sentences are followed by another sentence, so I wasn’t quite sure what you meant there. It seems to be a sticky issue and most people don’t offer up a rule at all, so I’d really like to know what you think!

I think you have two questions here:
1. Use only one space following a colon no matter what.
2. You’re right that I should have written, “If the sentence ending with a colon is followed by two or more closely related sentences, the first word of the sentence following the colon should be capitalized.”
Is that better?

Could you tell me if you would put a comma before and in the following sentence. Mary made a grocery list to buy the following ingredients: milk, butter, sugar and bread.

I am afraid that I am overusing commas. I feel like I am using them too much in the beginning of sentences. Here are the sentences I have questions with: 1. As a graduate of Wilkes University, I obtained my Bachelor of Arts Degree in Psychology and Elementary Education in May 2004. (do I need that comma in the beginning?) 2.. Prior to this employment, I completed two long-term teaching positions in the Dallas School District, both in a Kindergarten and Fifth grade classroom. (Do I need the comma after employment and after District?) 3. As a secondary learning support teacher, I have strengthened my skills in classroom management, particularly discipline procedures, and developed a strong understanding of the appropriate strategies needed to teach students of various skill levels. (Do I need the comma after teacher?) 4.As a co-teacher, I am responsible for learning the material in various content areas, without prior knowledge of the curriculum. (Do I need the comma after co-teacher?) 5. During my junior and senior year of college I spent time caring for a six year old boy with Down’s Syndrome. (Do I need a comma after college?) 6. In order to engage all students, I incorporate accommodations into lessons and activities, maintain effective communication with special and regular education staff, and ensure that IEP goals are properly met. (need the comma after students?) 7.With my qualifications and experiences in both special and regular education settings, I have developed into a more resourceful and confident educator. (need the comma after settings?) 8. It is with great anticipation that I am applying for a teaching position, on the elementary level, in your district. (do I need all of these commas here?) Thanks so much for any feedback you may have. I have been over analyzing this for days!

Megan, having seen Downes Syndrome, I decided to check the correct form and discovered Down Syndrome though open to correction, I believe the US doesn’t capitalise ‘syndrome’.

Although, the Chicago Manual of Style recommends writing Down syndrome, they add “The possessive forms Alzheimer’s, Down’s, Hodgkin’s, and the like, though less common in medical literature, may be preferred in a general context.”

#1 yes
#2 yes; also “fifth-grade classroom”
#3 yes
#4 The comma after “areas” is optional
#5 Place a comma after “college”; also, “six-year-old boy”
#6 yes
#7 yes
#8 Leave out the comma after “level.”