Questions
Learn how a question requests information, why the word order often changes, and the difference between a yes/no question and a wh- question.
Requesting information
A question asks the reader for something.
A question is a sentence that requests information. Unlike a statement, which gives information, a question is written to receive it.
In the sentence Does the train leave at noon?, the auxiliary verb does moves in front of the subject the train, and the sentence ends with a question mark rather than a period.
Questions fall into two broad groups: those that can be answered with yes or no, and those that ask for a specific piece of information using a question word.
Before you begin
Questions are one of four sentence types.
This lesson focuses on questions specifically. Sentence types as a whole include three other categories, each covered in its own lesson.
If you would like an overview of how sentence types work in general, begin with the Sentence Types page.
The central idea
The same information can be told, or asked for.
Compare a statement with the same idea turned into a question.
01
Statement
The train leaves at noon.
02
Question
Does the train leave at noon?
The useful question is: what moved, and what was added?
The auxiliary verb does has moved in front of the subject, and the sentence now ends with a question mark. The core words of the sentence stay largely the same.
Yes/no questions
These questions can be answered with yes or no.
An auxiliary verb moves before the subject
Is she at home?
The verb is comes before the subject she.
Do, does or did is added when there is no other auxiliary verb
Did he call the office?
The main verb called returns to its base form, call, once did is added.
The answer is expected to be yes or no
Yes, she is. / No, he did not.
Wh- questions
These questions ask for a specific piece of information.
who → asks about a person
what → asks about a thing or an action
where → asks about a place
when → asks about a time
why → asks about a reason
how → asks about a manner, method or amount
The question word comes first
Where does the train leave from?
The question word is placed at the front of the sentence, followed by the same subject-auxiliary inversion used in a yes/no question.
Going further with questions
This lesson introduces how questions are formed.
Alongside yes/no and wh- questions, English also uses question tags and indirect questions. These patterns, along with a closer look at question word order, are covered in their own section.
A closer look at forming questions
The Question Formation section covers yes/no questions, wh- questions, question tags and indirect questions in greater depth.
A useful decision guide
Ask what the sentence is doing, and how it is formed.
01
Is the sentence requesting information?
If so, and not simply giving it, the sentence is likely a question.
02
Can the answer be yes or no?
If so, an auxiliary verb belongs before the subject.
03
Is a specific piece of information being asked for?
If so, a question word belongs at the front of the sentence.
04
Does the sentence end with a question mark?
A question ends with a question mark, not a period.
Common mistakes
A question needs the right word order and the right punctuation.
The auxiliary verb must move before the subject.
Not: She is at home?
Correct: Is she at home?
Without the inversion, the sentence reads as a statement, even with a question mark.
The main verb returns to its base form after do, does or did.
Not: Did he called the office?
Correct: Did he call the office?
Once did carries the past tense, the main verb no longer needs its own past ending.
A question ends with a question mark, not a period.
Not: Where does the train leave from.
Correct: Where does the train leave from?
Check your understanding
Which sentence type is shown below?
Choose the correct answer for each sentence.
Have you finished the report?
✅ Exactly! The auxiliary verb have comes before the subject, and the sentence requests information.
❎ Not quite. Check the position of the subject and the auxiliary verb.
Is information being given, or asked for?
Why did the meeting start late?
✅ Exactly! Why asks for a specific reason, not a yes or no answer.
❎ Not quite. Could this question be answered with just yes or no?
Look at the first word of the sentence.
Can you attend the meeting on Friday?
✅ Exactly! This question can be answered with yes or no.
❎ Not quite. There is no question word such as who or where here.
Could you answer this question with just “yes” or “no”?
Choose the best explanation
Select the sentence that explains the question correctly.
Why is “She is at home?” not a correctly formed question?
✅ Exactly! A question mark alone is not enough; the auxiliary verb needs to move in front of the subject.
❎ Not quite. Compare the word order to a correctly formed question.
Why does “Did he called the office?” need to be corrected?
✅ Exactly! Did already carries the past tense, so called should return to call.
❎ Not quite. Look closely at the form of the main verb.
Try it another way
Complete each question.
Type the missing word.
✅ Exactly! Does is needed since there is no other auxiliary verb in the sentence.
❎ Not quite. Think about the auxiliary verb needed with a singular subject in the present tense.
✅ Exactly! Where asks for a specific place.
❎ Not quite. The answer this question is looking for is a place.
Quick review
A question requests information, with a changed word order.
A question is a sentence that requests information and ends with a question mark.
A yes/no question moves an auxiliary verb before the subject and can be answered with yes or no.
A wh- question begins with a question word, such as who, what or where, followed by the same subject-auxiliary order.
When there is no other auxiliary verb, do, does or did is added, and the main verb returns to its base form.
Remember
Ask whether information is being requested, and how the sentence signals that.
A question requests something the reader does not yet know. That purpose is signalled by the position of the auxiliary verb, or by a question word, and confirmed by the question mark at the end.