Particularities of the verb forms

1. ‘to do’ can be an auxiliary verb and lexical (main) verb.
2. When ‘to do’ appears as the main verb, it also requires ‘to do’ as an auxiliary verb in the present simple and past simple tense for negative and interrogative sentences (example: “I didn’t do” or “Does he do?”).

Forms of the irregular verb ‘to do’ in all tenses

The verb ‘to do’ is a very frequent and essential verb. It is often a cause for misunderstandings, so all its forms in all tenses are listed here. The tables also highlight the particular forms that differ from the repeating ones. For clarification, the grammatical persons are presented as follows:

Number	Person
Singular	1 I 2 you 3 he, she, it
Plural	1 we 2 you 3 they

Forms in the present

Tense	Person and subject	Simple	Progressive/continuous
Present	1 I 2 you 3 he, she, it 1 we 2 you 3 they	do do does do do do	am doing are doing is doing are doing are doing are doing
Present perfect	1 I 2 you 3 he, she, it 1 we 2 you 3 they	have done have done has done have done have done have done	have been doing have been doing has been doing have been doing have been doing have been doing

• Information: Negations are formed with the auxiliary ‘to do’ and its forms ‘don’t/doesn’t’. The main verb ‘do’ in the infinitive follows.

Forms in the past

Tense	Person and subject	Simple	Progressive/continuous
Past	1 I 2 you 3 he, she, it 1 we 2 you 3 they	did	was doing were doing was doing were doing were doing were doing
Past perfect	1 I 2 you 3 he, she, it 1 we 2 you 3 they	had done	had been doing

• Information: Negations in the past also require ‘didn’t’ as the auxiliary verb and the verb ‘do’ in its infinitive form.

Forms in the future

Tense	Person and subject	Simple	Progressive/continuous
Future (will)	1 I 2 you 3 he, she, it 1 we 2 you 3 they	will do	will be doing
Future (going to)	1 I 2 you 3 he, she, it 1 we 2 you 3 they	am going to do are going to do is going to do are going to do are going to do are going to do	am going to be doing are going to be doing is going to be doing are going to be doing are going to be doing are going to be doing
Future perfect	1 I 2 you 3 he, she, it 1 we 2 you 3 they	will have done	will have been doing

Infinitives and imperatives of ‘to do’

The imperative expresses commands and exists only in the 2nd person singular and plural, with its forms agreeing:

Person and subject	Imperative (affirmative)	Imperative (negated)
2 you 2 you	do do	don’t do don’t do

The infinitive is the base form and, like the participles, appears in different aspects:

Verb form (aspect)	Infinitive	Present participle	Past participle
Simple	to do	doing	done
Progressive	to be doing	–	–
Perfect	to have done	having done (perfect participle)	–
Perfect progressive	to have been doing	having been doing	–