Do, Does, Did: Mastering Auxiliary Verbs in English
Use does with he, she, it and singular nouns in the present; use do with I, you, we, they and plural nouns; use did with every subject in the past. After any of the three, the main verb goes back to its base form: Does she work? (not works), He didn’t go (not went). That one rule fixes most learner mistakes with do, does and did.
Quick chart
| Subject | Present | Past |
|---|---|---|
| I, you, we, they, plural nouns (the kids) | do / don’t | did / didn’t |
| he, she, it, singular nouns (my dad, the dog) | does / doesn’t | did / didn’t |
Quick test: if you would add -s to the verb in a normal sentence (she plays), use does in the question or negative (Does she play? She doesn’t play.). The -s moves from the verb to do. In the past there is no choice to make: did for everyone.
1. Yes/no questions
Pattern: Do/Does/Did + subject + base verb?
| Statement | Question |
|---|---|
| You like coffee. | Do you like coffee? |
| They live near here. | Do they live near here? |
| She speaks Spanish. | Does she speak Spanish? |
| It rains a lot in April. | Does it rain a lot in April? |
| Your brother works here. | Does your brother work here? |
| You called your mother. | Did you call your mother? |
| He studied for the exam. | Did he study for the exam? |
| The train left on time. | Did the train leave on time? |
| We won last night. | Did we win last night? |
Notice the last three: called, studied, left and won lose their past form because did already carries the past.
2. Wh- questions
Pattern: question word + do/does/did + subject + base verb?
- Where do you work?
- What time does the shop open?
- Why did she leave early?
- How do you spell your name?
- How much does this cost?
- When did they get married?
- What did you have for lunch?
When there is no do/does/did
If who or what is the subject of the question, you do not use an auxiliary:
- Who called you? (someone called you) – not Who did call you?
- What happened? – not What did happen?
- Who lives here? – not Who does live here?
Compare: Who did you call? Here you is the subject and who is the object, so did is needed.
3. Negative sentences
Pattern: subject + don’t/doesn’t/didn’t + base verb.
| Positive | Negative |
|---|---|
| I like spicy food. | I don’t like spicy food. |
| We need more sugar. | We don’t need more sugar. |
| He plays the guitar. | He doesn’t play the guitar. |
| The bus stops here. | The bus doesn’t stop here. |
| My phone has a camera. | My phone doesn’t have a camera. |
| They finished the project. | They didn’t finish the project. |
| She went to the party. | She didn’t go to the party. |
| I saw the message. | I didn’t see the message. |
In speech and most writing, use the contractions don’t, doesn’t and didn’t. The full forms do not, does not, did not sound formal or strongly emphatic.
Negative questions
Put the contraction first: Don’t you like it? Doesn’t he know? Didn’t they call? These usually show surprise or expect the answer “yes”. The uncontracted form moves not after the subject: Do you not like it? (more formal, common in British English).
4. Short answers
Answer a do/does/did question with the same auxiliary, not the main verb:
| Question | Yes | No |
|---|---|---|
| Do you speak French? | Yes, I do. | No, I don’t. |
| Does he live here? | Yes, he does. | No, he doesn’t. |
| Did they arrive on time? | Yes, they did. | No, they didn’t. |
| Does it hurt? | Yes, it does. | No, it doesn’t. |
Avoid Yes, I speak. or Yes, I like. They sound incomplete in English.
5. Emphasis
In a positive sentence you normally leave out do. Put it back in, stressed, to insist, contradict or show strong feeling:
- I do want to come – I’m just busy tonight.
- She does care about you, even if she doesn’t show it.
- He did try his best.
- “You never listen.” – “I do listen!”
- Do sit down. (a warm, polite invitation)
The main verb is still the base form: she does care, not she does cares.
6. Avoiding repetition
Do, does and did can stand in for a whole verb phrase you just mentioned:
- She practises every day, and so do I.
- I don’t eat meat, and neither does my sister.
- He likes jazz more than I do.
- “I loved that film.” – “So did I.”
- You said you’d call, but you didn’t.
Question tags
For a present or past simple sentence, the tag uses do/does/did, flipped positive to negative:
- You live in London, don’t you?
- She works from home, doesn’t she?
- They didn’t win, did they?
- He forgot again, didn’t he?
Do as a main verb
Do is also an ordinary verb meaning “perform, carry out”: do homework, do the dishes, do your best, do exercise. Its forms are do / does / did / done / doing. When do is the main verb, you can end up with two of them, and that is correct:
- What do you do? (What is your job?)
- Does he do his homework on time?
- I didn’t do anything wrong.
- What did you do at the weekend?
The first one is the auxiliary, the second is the main verb in base form.
When you don’t use do, does or did
| Situation | Correct | Wrong |
|---|---|---|
| with be | Are you tired? She isn’t here. Was it good? | Do you be tired? She doesn’t be here. |
| with modals (can, will, should, must…) | Can you swim? He won’t come. | Do you can swim? He doesn’t will come. |
| with other tenses that already have an auxiliary | Have you finished? Is she working? | Do you have finished? Does she working? |
| in plain positive statements | I like tea. He went home. | I do like tea. (only for emphasis) |
Have as a main verb (possession) does take do: Do you have a car? She doesn’t have time. British English also uses Have you got a car?
Sentence examples by situation
Talking about routines (present simple)
- Do you get up early on weekdays? – Yes, I do. I start work at seven.
- Does your son walk to school? – No, he doesn’t. He takes the bus.
- We don’t watch much TV during the week.
- My grandmother doesn’t use a smartphone.
- How long does it take you to get to work?
Talking about the past (past simple)
- Did you sleep well? – Not really. The neighbours had a party.
- We didn’t have time to visit the museum.
- What did the doctor say?
- I didn’t know you could cook!
- Where did you buy that jacket?
At work or school
- Does anyone have questions?
- Did you send the report? – Yes, I did. I sent it this morning.
- The printer doesn’t work again.
- Do we need to bring our laptops tomorrow?
Shopping and travel
- Do you take credit cards?
- Does this train stop at the airport?
- How much did your flight cost?
- The hotel doesn’t include breakfast.
Present or past: do/does or did?
Look for a time word. Habits, facts and timetables take do/does: every day, usually, often, never, on Mondays. Finished past events take did: yesterday, last week, in 2019, two days ago, when I was a child.
- Do you usually cook dinner? (habit) / Did you cook dinner last night? (one past evening)
- She doesn’t drink coffee. (fact about her) / She didn’t drink her coffee. (that one cup, earlier)
With ever and yet about experience up to now, British English prefers the present perfect (Have you ever been to Peru?); American English often uses did with yet (Did you eat yet?).
Common mistakes
| Wrong | Right | Why |
|---|---|---|
| Does she likes pizza? | Does she like pizza? | the -s is already on does |
| He don’t know. | He doesn’t know. | third person singular takes does (he don’t is non-standard) |
| Did you went there? | Did you go there? | did + base form |
| I didn’t saw it. | I didn’t see it. | only one past marker |
| Do he work here? | Does he work here? | he → does |
| Where you live? | Where do you live? | the auxiliary can’t be dropped |
| Who did break the window? | Who broke the window? | who is the subject |
| Does the children play outside? | Do the children play outside? | children is plural |
| My family do… / My family does… | both | British English often treats group nouns as plural; American English uses does |
Practice
A. Fill in do, does or did.
- ___ your sister live in Madrid?
- What ___ you eat yesterday?
- They ___n’t like horror films.
- ___ it snow much where you live?
- I ___n’t hear the alarm this morning.
- How often ___ the buses run?
- “Did you enjoy it?” “Yes, I ___.”
- Your dog doesn’t bite, ___ it?
Answers: 1. Does 2. did 3. do 4. Does 5. did 6. do 7. did 8. does
B. Correct the sentence.
- Does he plays tennis?
- She didn’t came to class.
- Do you can help me?
- Why you are late?
- Who did tell you that?
Answers: 1. Does he play tennis? 2. She didn’t come to class. 3. Can you help me? 4. Why are you late? 5. Who told you that?
C. Make questions. 1. He drives to work. 2. They bought a new car. 3. The film starts at eight. (When…?)
Answers: 1. Does he drive to work? 2. Did they buy a new car? 3. When does the film start?
For a full worksheet with more items, see the do and does exercise worksheet.
Quick answers
Is did an auxiliary verb?
Yes, in questions, negatives, short answers and emphasis (Did you see it? I didn’t.). It is also the past tense of the main verb do (I did my homework).
Do or does with you?
Always do, whether you means one person or several: Do you know her?
Do or does with everyone, nobody, each?
These are singular, so does: Does everyone have a pen? Does anybody know the answer? Nobody is already negative, so don’t add doesn’t: say Nobody knows, not Nobody doesn’t know.
Why is it “Does she have” and not “Does she has”?
Because does already shows third person singular. Only one word in the verb phrase can carry the -s, and after any form of the auxiliary do the main verb is always the bare base form: have, go, like, want.
Can I say “I did go” in a normal sentence?
Only for emphasis or contrast, such as I did go to the meeting – you just didn’t see me. In a plain statement, say I went to the meeting.
Do or does with names and things?
One person or thing takes does (Does Maria know? Does this bus go downtown?); two or more take do (Do Maria and Tom know?).
See how these auxiliaries fit with the other tenses in the verb tenses chart and in example sentences for all tenses.
