Unit 4.2
Do: Auxiliary verb
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An auxiliary verb is a helping verb that has no meaning on its own but it gives functional and grammatical meaning to the main verb.
Do as a main verb means to perform or to complete an action.
It can also be used as an auxiliary verb. Do as an auxiliary verb is used to form the negative and interrogative sentences of other verbs, as well as for emphasis and negative imperatives.
Form
The verb do as an auxiliary verb is followed by infinitives without to.
In its present form
It has three forms:
Affirmative (for emphasis)
{see Present and Past Emphatic Tenses, B1 level}
Negative
{see Present Simple, A1 level}
Interrogative
{see Present Simple, A1 level}
In its past form
It has three forms:
Affirmative (for emphasis)
{see Present and Past Emphatic Tenses, B1 level}
Negative
{see Past Simple, A1 level}
Interrogative
{see Past Simple, A1 level}
In the imperative
Negative (only in the present tense)
{see Imperative Mood,A1 level}
Example
- Negative
- I don’t speak Spanish.
- I didn’t hurt my neck.
- Interrogative
- Do you speak Spanish?
- Did you hurt your neck?
- Emphasis
- She does look nice today.
- She did break her leg yesterday.
- Negative imperative
- Don’t speak loudly!
Use
Do as an auxiliary verb is used:
- To form negatives of other verbs.
- To form interrogative sentences of other verbs.
- To give emphasis in an affirmative clause.
- To form negative imperatives in its negative form (don’t).
Summary
Do as an auxiliary verb is used to form the negative and interrogative sentences of other verbs. It is also used in an affirmative sentence to give emphasis. In its negative form (don’t), it can function as negative imperative but only in the present tense.
For examples:
— Interrogatives: “Do/Did you live in Brussels?“ = Do as an auxiliary verb is put before the subject to create an interrogative.
— Negative: “I don’t/didn’t like football.” = We use do as an auxiliary verb before the main verb to form a negative sentence.
— Emphasis: “You do/did look tired.” = We use do as an auxiliary verb before the main verb in an affirmative sentence to give emphasis.
— Negative imperative: “Don’t talk to me!” = Do in the negative form is used to form a negative imperative.
NOTE: We always use the negative form (don’t) for negative imperatives and it is always put at the beginning of the sentence.
Let’s revise this content in {Form} section. Take a look at {Example} section that shows its use within a context sentence.
