A wh-question asks for specific information rather than a yes-or-no answer. It begins with a question word — who, what, where, when, why, how, which, or whose — and follows a particular word order depending on what role the question word plays in the sentence.
The question words themselves are covered separately. This lesson focuses on how to build the question once you have chosen the right word.
The standard pattern
Most wh-questions follow this order:
Wh-word + auxiliary verb + subject + main verb
The auxiliary verb (do, does, did, is, are, was, were, has, have, will, can, should) comes before the subject. This flip is called inversion — the same mechanism that turns she does work into does she work?, with the question word added at the front.
In present simple and past simple, where there is no visible auxiliary in the statement, English inserts do / does / did to form the question.
| STATEMENT | QUESTION |
|---|---|
| She works in Berlin. | Where does she work? |
| They finished early. | When did they finish? |
| He plays tennis. | How often does he play tennis? |
Notice that the main verb returns to its base form: works becomes work, finished becomes finish. The tense marker moves to the auxiliary.
Subject questions vs object questions
This is the single most important distinction in wh-question structure.
Object questions
When the wh-word replaces the object (or another non-subject element), use the standard pattern with inversion and an auxiliary.
Subject questions
When the wh-word replaces the subject itself, there is no inversion and no added auxiliary. The question keeps the same word order as a statement — the wh-word simply takes the subject's place.
Compare the two directions for the same situation. James broke the window:
- Object question: What did James break? — asking about the object (the window)
- Subject question: Who broke the window? — asking about the subject (James)
The object question uses did and inversion. The subject question uses neither.
How to tell the difference
Ask yourself: does the wh-word replace the person or thing doing the action, or the person or thing receiving it?
- Replaces the subject (the doer) — no auxiliary, no inversion: Who wrote this email?
- Replaces the object or another element — add auxiliary, invert: What did she write?
A practical test: if you can answer the question by placing a name directly where the wh-word is, and the result is a normal statement, it is a subject question.
Questions with be, have, and modals
When the statement already contains be, have (as an auxiliary), or a modal verb (can, will, should, might), that verb moves before the subject. No do / does / did is needed.
The auxiliary that is already present does the job of inversion by itself.
How + adjective or adverb
How combines with an adjective or adverb to ask about degree, quantity, frequency, or distance. The rest of the question follows the standard pattern.
These are regular object-type questions — how old, how far, how often acts as the wh-phrase, and the auxiliary + subject + verb follow in the usual order.
Questions with prepositions
When a verb or adjective normally takes a preposition, the preposition moves to the end of the question in everyday English.
Placing the preposition at the front (At what are you looking?) is grammatically possible but sounds very formal and is rare in speech. The end position is the natural choice at this level.
Common mistakes
Missing auxiliary in object questions
Adding an unnecessary auxiliary in subject questions
Forgetting to use the base form after do / does / did
Wrong word order with be and modals
Preposition dropped or misplaced