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How to punctuate


Correct punctuation increases clarity

There's a good chance you punctuate poorly and don't realize it.

This page will fix your mistakes. It covers the top ten rules of punctuation.

But let's consider why you should care about punctuation in the first place:

♖ Good writing is an indicator of an organized mind that is capable of arranging information in a systematic fashion to help other people understand things. — Dustin J. Mitchell
♖ Clear writing leads to clear thinking. You don’t know what you know until you try to express it. — Michael A. Covington
♖ If you are deciding between two people to hire, always choose the better writer. Assuming they are equally qualified, the better writer will communicate work issues more clearly. This extends to emails, messages — frankly, everywhere. — David Heinemeier Hansson

Don't take punctuation too seriously

Let’s also clarify what’s not important: The lesser-known rules of grammar and punctuation that instruct us to write in ways that differ from everyday speech .

In practice, no one cares if you start a sentence with “and”  —  because that’s how people talk. By definition, there’s usually no loss in clarity by communicating naturally.

There is, however, loss of clarity when transposing speech to writing without respect for the purpose of punctuation: being clearly understood.

You'll see how misusing punctuation not only confuses readers but also marks you as someone who doesn’t pay attention to detail. 

Let's begin with punctuation rule number one. I'm going to use absurd examples to keep this post fun.

1. Separate danglers with a comma

A “dangler” is my term for a word located at the extreme end of a sentence that either:

Examples of addressing someone being spoken to

Correct: “Matt, you eat way too many pickles.”

Correct: “Why do you keep touching my belly button, Matt?”

In both examples, the person being spoken to is referenced at either extreme end of the sentence. Notice that the word used to address the person (e.g. “Matt”) is separated from the rest of the sentence with a comma. 

Always do this. If you don’t, you could run into the following problem:

Potentially confusing: “Let’s eat grandpa.”

Very clear: “Let’s eat, grandpa.”

Potentially confusing: “Where’s the kitchen Matt?”

Very clear: “Where’s the kitchen, Matt?”

Notice how the above two sentences have entirely different meanings based on the presence of a comma. The confusing example can be mistaken for, “Where is the kitchen mat [that I stand on while cooking]?” as opposed to, “Hey, Matt, where exactly is the kitchen located?”

Comma rules make up the bulk of this page. Because not knowing when to use a comma is the most common punctuation mistake.

Examples of answering a question with an affirmative or negative word

Correct: “Yeah, he smelled like burned sausage.”

Correct: “Correct, I’m still waiting for Santa Claus’ lawyer.”

Correct: “I don’t know what you’re talking about, no.”

In the above examples, a positive (“yes”, “yeah”, “sure”, “correct”, etc.) or negative (“no”, “nah”, “nope”, “incorrect”, etc.) word begins or ends the sentence. As when addressing someone, always separate the affirmative or negative word from the rest of the sentence using a comma. 

If you don’t, you could end up with confusion:

Potentially confusing: “No one is still here.”

Clear: “No, one is still here.”

In the first example, you’re stating that nobody is here. In the second, you’re responding to a question in the negative (“no”) then clarifying that “one [person] is still here.”

2. If you can, use a period instead of a comma or a hyphen

Never use a comma or a hyphen if using a period in its place wouldn’t change the sentence’s intended meaning. Following this rule will help you avoid several grammar mistakes.

Consider these examples:

Incorrect: “I don’t know why he’s singing, he’s really bad at it.”

Incorrect: “I’m not a liar, I just don’t respect the truth.”

Incorrect: “I have a feeling that you stink — am I right?”

Incorrect: “Why would you do that, that’s silly.”

Read through those sentences once more. This time, imagine replacing each comma or hyphen with a period. The statements continue to read perfectly, right? The sentences’ meanings don’t change at all, right? 

Awesome. Then use that period instead of the comma/hyphen, and you’ve just confidently avoided improper comma usage!

(I’m not going to dive into how it is that you’re avoiding grammatical errors because that would necessitate a discussion on clauses, and I want to keep this guide short.)

Here are the fixed examples:

Correct: “I don’t know why he’s singing. He’s really bad at it.”

Correct: “I’m not a liar. I just don’t respect the truth.”

Correct: “I have a feeling that you stink. Am I right?”

Correct: “Why would you do that? That’s stupid.”

The takeaway here is very simple: Unless you’re an experienced writer, train yourself to always take a second look whenever you use a comma or a hyphen. Ask yourself, “Can I replace this with a period?” If so, do it. This is the most important comma rule.

3. In a list, use a comma before the final “and”

When you have a series of items separated by commas, ensure that you place a final comma (an “Oxford comma”) before and:

Correct: To my parents, Jeff Bridges, and Wonder Woman.

Incorrect: To my parents, Jeff Bridges and Wonder Woman.

In the correct example, you’re dedicating a book to your parents, and Jeff Bridges, and Wonder Woman. That’s three individual people.

In the incorrect example, you’re dedicating a book to your parents who you’re then identifying as Jeff Bridges and Wonder Woman. The lack of a concluding comma inadvertently changes the entire meaning of your sentence.

Takeaway: At the end of a list of items, always use a comma before the final “and.”

4. Use a comma before introducing a question

Place a comma before introducing a question — regardless of whether the question is wrapped in quotation marks:

Correct: I’ve been wondering, How does one truly pick their toes?

Incorrect: I’ve been wondering how does one truly pick their toes?

Correct: He was wondering, “Where are my hands?”

Tip: Quotes only surround a question when you’re word-for-word quoting something that was said. If you’re instead hypothetically posing a question, as is the case in the first example, then quotes are not needed.

5. Don’t use a comma to represent vocal pauses

Commas serve many purposes, but representing arbitrary pauses in speech is not one of them. For example, this is not when you should use a comma:

Incorrect: “It’s a tough day in a man’s life, when he finds out he’s a robot.”

Correct: “It’s a tough day in a man’s life when he finds out he’s a robot.”

The above sentence might be spoken with a pause between the words “life” and “when” in order to provide dramatic effect, but a comma is the wrong form of punctuation to capture a pause. Instead, an ellipsis (…) would be appropriate:

Correct: “It’s a tough day in a man’s life… when he finds out he’s a robot.”

The easiest way to avoid misusing commas in this manner is to ask yourself if using the comma makes the sentence read like a haiku. If so, replace it with an ellipsis or drop it altogether.

This leads into the next rule…

6. Don’t use ellipses

An ellipsis is a trio of periods (…).

Don’t use it—unless you're quoting someone. You rarely see it used in textbooks , because it’s the sign of a lazy writer failing to structure their thoughts so that they fall within the lines of more common punctuation. 

In essence, the writer is falling back on free-form speech patterns. Speaking of which, that's the one place it’s okay to use an ellipsis: inside a quote.

For example, she said to me, “Dianna… You need to get rid of that damn cat.”

Above, the purpose of the ellipsis is to insert a dramatic pause reflecting how the quote was originally articulated. In this way, it serves to properly capture the intention behind breaking Rule #5.

Don’t use ellipses in formal writing. Only consider using them within quoted speech.

To see examples of great writing and punctuation, read the first page of my How to Build Muscle or Startup Growth Hacking guides. I spent hundreds of hours on them.

7. Avoid semicolons

It’s really easy to use semicolons [;] incorrectly, so my advice is to not use them in the first place. After all, semicolons are rarely needed to help communicate a point.

Since it would be pedantic to not at least provide you with one example of proper semicolon usage, I will show you the case where it’s difficult to misuse it: when you’re connecting two sentences that use different sets of words to express the same idea.

Correct: “She’s not a good listener; I feel like I’m talking to myself.”

Correct: “I can’t stop thinking about my dog; she means everything to me.”

Incorrect: “That shade of brown looks like dirt; it smells bad too.”

Incorrect: “That person looks like a hamster; he’s weird.”

Notice how the correct examples use a semicolon to conjoin two sentiments that are essentially making the same point but from different perspectives. (Sometimes this is desired for the purposes of emphasis.) This is when you would use a semicolon.

In contrast, notice how the incorrect examples use a semicolon to conjoin two sentiments that convey complementary but not redundant information. “That person looks like a hamster” is one sentiment. “He’s weird,” although perhaps related in thought, is a separate sentiment. They are not mere rewordings. Do not use a semicolon here.

If we wanted to correctly use a semicolon for the last incorrect example, we could change the second part to, “That person looks like a hamster; he has rodent-like qualities.” In this way, we’re specifically describing what a hamster looks like instead of explicitly using the word “hamster.”

The primary takeaway from this rule is simple: Avoid using semicolons because they invite redundancy.  Redundancy is bad in writing. Find a way to express yourself concisely. Further, when a semi-colon is used in this way, it can often be seamlessly substituted for a period. And a period is better than a semi-colon because readers are more familiar with them and are therefore less likely to pause to assess why you're using a semi-colon.

8. Only use colons for standalone sentences

Only use a colon when you’re presenting an example of what the words before the colon refer to:

Correct: “There is only one God: Thor.”

Correct: “She had one piece of advice for me: Never slap a monkey.”

Correct: “This is how you play footsy: with your feet.”

Correct: “He is a very smart man: He solves sudokus within seconds, he speaks five languages, and he’s great with numbers.”

There's also a second colon rule at work here: The words before the colon must be able to stand alone as a grammatically correct sentence. Meaning, if you replace the colon with a period, the words before the period make sense when read alone.

For example, below is incorrect colon usage:

Incorrect: “Her favorite color was: blue.”

Incorrect: “I don’t like purple people because: they are inferior.”

In these incorrect examples, the leading sentence couldn’t stand alone without adding words back in:

In both of these incorrect examples, simply drop the colon and the sentence will magically read perfectly. (If punctuation serves zero grammatical purpose, don’t use it!)

The takeaway: Only use colons when you’re connecting a standalone leading sentence proceeded by an example of what that sentence refers to.

9. Place ending punctuation inside quotation marks

American English dictates that punctuation (periods, exclamation marks, and question marks) should be placed inside quotation marks:

Correct: He said to me, “That’s one hell of a goat.”

Incorrect: He said to me, “That’s one hell of a goat”.

Correct: He asked, “Life sucks. Why am I so short?”

Incorrect: He asked, “Life sucks. Why am I so short”?

Correct: He yelled to the driver, “Go back to America!”

Incorrect: He yelled to the driver, “Go back to America”!

If you live in the UK, the rule is reversed: place the punctuation outside of the quotes.

10. Punctuate within full-sentence parentheses

If you’re wrapping a full sentence within parentheses, the final punctuation must stay within those parentheses:

Correct: John is stupid. (He scored 35 on an IQ test.) He’ll die young.

Incorrect: John is stupid. (He scored 35 on an IQ test). He’ll die young.

In contrast, if you’re wrapping merely a portion of a sentence in parentheses, leave the sentence’s ending punctuation outside the parentheses:

Correct: I’m going back home (Japan).

Incorrect: I’m going back home (Japan.)

To see examples of great writing and punctuation, read the first page of my How to Build Muscle or Startup Growth Hacking guides. I spent hundreds of hours on them.

Bonus: Eliminate words

Great writing consists only of needed words. For example, notice how many words in the following passage serve little purpose.

(Original text by Simon Heffer. Edits by Tom Freeman.)

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