Question Marks: When to Use Question Marks in Writing (Examples)

If you want to learn about question marks and know how and when to use them, this article is for you. We'll cover everything you need to know to use them correctly in your writing.

In short:

• Question marks are used to mark the end of an interrogative sentence. In other words, use them at the end of a question.

This guide is part of our free online Grammar Book.

When to Use Question Marks

Question marks are one of three types of punctuation that you can use to end your sentence. The other two are the exclamation mark and the period. Each of these punctuation marks is used with a specific type of sentence, and for question marks, that's... you guessed it, questions. But when should you use them?

Use Them With Questions

Questions are pretty discernable when you ask them out loud because there's an inflection in your voice towards the end of the sentence. Your tone goes into the higher notes. Because you can't hear someone's tone of voice when reading a sentence, the question mark is how you can tell it's a question. Think of the question mark as the written form of that voice inflection. Of course, a lot of the time, it's evident that a sentence is a question.

Look at the following question as an example; the 'wh-word at the start gives it away:

What's your name?

But it's not always that clear-cut.

For instance:

Sam isn't coming after all?

Oh, you've got a dog?

There are two different types of questions: open questions and closed questions. In both cases, you'll use a question mark.

Let's have a look at some examples:

Where did you find your personal trainer?

Shall we grab coffee tomorrow morning?

Did your date go well?

As you can see, the question mark goes right at the end of the sentence.

Don't Use Them With Indirect Questions

An indirect question is a question inside a statement. It's a way of asking a question without asking a question.

Like in the following sentence:

I was wondering whether you'd like to go to the prom with me.

Or, you can use it to tell somebody about a question that was asked.

Case in point:

He asked me if I'd go to prom with him.

I asked him if the sky was blue.

Indirect questions are actually classed as declarative sentences, not interrogative. Therefore, you don't end them with a question mark but a period.

Use Them to Show Uncertainty

You can use a question mark in brackets to show that you aren't sure of the information you just gave or even confused by it.

Let me illustrate:

Mary quit her job (?) and is having a crisis, so we need to head over to hers right away. 

When John first arrived in California (1976?) he got a job at the bowling alley.

Apparently, we're the first ones to arrive (?).

Rules for Question Marks

The basic rules for using question marks are:

• Use them at the end of a sentence, directly after the last word
• Follow them with a space
• Capitalize the first word after a question mark

But if you want to go deeper than that (which I know you do because that's why you're here), then read on.

Question Marks and Quotation Marks

Quotation marks can get a little tricky because their role is to quote what someone else said or to cite titles. This means that whatever punctuation is already present must remain, regardless of which category your sentence falls into.

• If the quote itself isn't a question, but the sentence is, then the question mark should sit outside the quotation marks.

This is illustrated in the following sentence:

Why did Pedro say, "I was at the office doing overtime"?

But if the quote is a question contained within a question, should you use two question marks? The answer is no. You use one to stand in for both and place it before the quotation marks. This is the only time the question mark isn't the thing ending the sentence.

Why did Pedro ask, "Did you know I was working overtime last night?"

What if you had a declarative sentence containing a quote with a question mark? The question mark serves to finalize the sentence, and we won't use a period.

I've just finished reading "They Shoot Horses, Don't They?"

Question Marks and Parentheses

Parentheses - also known as brackets - are a great way to add some non-essential information into a sentence. In other words, the sentence is grammatically complete without the information in brackets, but the info adds value.

When using question marks with parentheses, the rule's pretty straightforward. Does the question mark apply to the information within the brackets? If so, insert the question mark before you close the bracket. Does the question mark apply to the broader sentence? If so, add the question mark after the brackets.

Here's an example for each:

We're going to have lunch at the Roundhouse (do you know where that is?).

Would you like to have lunch at the Roundhouse (on First Avenue)?

Question Marks with Other Punctuation

Sometimes you might see a question mark followed by another question mark or a question mark followed by an exclamation mark.

Like in the following sentences:

Have you seen what she's wearing??

How many times must I tell you not to rock on your chair?!

The double question marks in the first sentence help express shock or surprise.

The question mark followed by an exclamation mark (also known as an interrobang when combined into a single punctuation mark like this: ‽) is a way to make a question exclamatory. In other words, you're still asking a question, but the exclamation mark helps add emotion to it, like anger, disgust, or joy, just like any exclamatory sentence.

It's worth noting that while these punctuation combinations are okay to use in informal writing, you wouldn't usually use them in formal contexts.

Concluding Thoughts

That concludes this article on question marks and their usage. I hope you found it helpful.

Let's summarize what we've learned:

• Question marks are to be used with interrogative sentences, otherwise known as questions.
• You can also use a question mark within parentheses to show confusion.
• With quotation marks and parentheses, if the question mark applies to the sentence contained within them, you should also place the question mark within them. If it applies to the broader sentence, put the question mark after you've closed the brackets or quotation marks. 
• Use double question marks or question marks followed by an exclamation mark sparingly and only in informal contexts.

If you enjoyed this article, be sure to check out our Grammar Book, a free online database of grammar articles.