Unit 4.2

Auxiliary use of Need

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A modal verb is a type of auxiliary (helping) verb that has no meaning on its own but it modifies the main verb, changes his meaning and gives more details about the action.

The verb need is both an ordinary verb and an auxiliary-modal verb.


Need, as an auxiliary-modal, always has the same form even for the third person.

When we use need as a modal verb:

  1. we do not find the to + verb after need;
  2. we form question and negative forms without the auxiliary do;
  3. we don’t apply the -ing form to need;
  4. we don’t add an -s for the third person singular;
  5. we almost always use a negative word (e.g. nobody, no one, nothing) or phrase in the clause, even if the verb phrase is affirmative.

Need as an auxiliary verb has three forms: affirmative, negative and interrogative.


Its structure, in the affirmative form, is:
Subject + need + base form of the verb

I/You need work
He/She/It need work
We/You/They need work


Its full structure, in the negative form, is:
Subject + need + not + base form of the verb

Negative short form is: Needn’t
Subject + needn’t + base form of the verb

I/You need not
He/She/It need not work
We/You/They need not work


Its structure, in the interrogative form, is:
Need + subject +base form of the verb + ?

Need I/you work ?
Need he/she/it work ?
Need we/you/they work ?




  • You need pay for it. 
  • Nobody need worry about the crisis.
  • No one need know that you are here.


  • I need not stay any longer.
  • She need not have come here. 
  • We need not tell anyone. 


  • Need we worry about the wound?
  • Need she come again?
  • Need we say anything more?


We use need as an auxiliary-modal verb when we refer to immediate necessity, ask for or give permission and when we make decisions about the future.


We can use need as an auxiliary and as an ordinary verb. Need expresses immediate necessity, permission and decisions about the future.

When used as an auxiliary verb, we have to remember that it accompanies the main verb, does not need to if followed by an infinitive, does not require the ending –s when we are using the third person singular and is mainly used in the negative and interrogative forms (without using the auxiliary verb do).

We can use it in its different forms:

  • affirmative: we start with the subject followed by need and a complement;
  • negative: we start with the subject followed by need not and a complement;
  • interrogative: we start with need followed by the subject and a complement (the sentence ends with a question mark).

For example:
— Affirmative: “She need drink more water.”
— Negative: “She needn’t drink more water.”
— Interrogative: Need she drink more water?
♦ “She ought to drink more water.” = If we use the auxiliary ought to then we do not talk about a necessity, but we give an advice to her to drink more water.

Let’s revise this content within the {Form} section. Take a look at the {Example} section that shows its use within a context.


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