do in English – auxiliary and main verb

Is do an auxiliary or a main verb?

The verb do can be an auxiliary verb or a main verb in English.

1. do as a main verb

1.1. do as a main verb in Simple Present (do, does, don't, doesn't)

Pronouns Affirmative sentences Negative senteces Questions
I I do my homework. I do not do my homework.* Do I do my homework?*
you You do your homework. You do not do your homework.* Do you do your homework?*
he, she, it He does his homework. He does not do his homework.* Does he do his homework?*
we, you, they They do their homework. They do not do their homework.* Do they do their homework?*

1.2. do as a main verb in Simple Past (did, didn't)

Pronouns Affirmative sentences Negative senteces Questions
I, he, she, it, we, you, they She did her homework. She did not do her homework.** Did she do her homework?**

1.3. do as a main verbpast participle (done)

Pronouns Affirmative sentences Negative senteces Questions
I, you, we, you, they We have done the shopping. We have not done the shopping. Have we done the shopping?
he, she, it He has done the shopping. He has not done the shopping. Has he done the shopping?

1.4. do as a main verb (Present Progressive, Gerund, present participle) – (doing)

affirmative negative
I am doing my homework. I am not doing my homework.
Doing my homework is not always fun. Not doing my homework is not clever.
I saw Jane doing her homework. I didn't see Jane doing her homework.

2. do as an auxiliary

2.1. do as an auxiliary in negations in the Simple Present

I don't do my homework in the evenings.*

2.2. do as an auxiliary in negations in the Simple Past

I didn't do my homework yesterday evening.**

2.3. do as an auxiliary in quesions in the Simple Present

Do you like rugby? – Does he like rugby?

2.4. do as an auxiliary in quesions in the Simple Past

Did you see Peggy yesterday?
When did you get up this morning?

2.5. do with the negative imparative

Don't sing under the shower.


* Here we use do in the negative sentence as an auxiliary and do as a main verb.

** Here we use did in the negative sentence as an auxiliary and do as a main verb.