Needis a semi-modal verb because in some ways it is like a modal verb and in other ways like a main verb.
We useneedmostly in the negative form to indicate that there is no obligation or necessity to do something:
Youneedn’ttake off your shoes.
Need: form
Affirmative form
Affirmatives with the semi-modalneedare not common and they are used in formal contexts. There is almost always a negative word (e.g.no one, nobody, nothing) or phrase in the clause, even if the verb phrase is affirmative:
No oneneedthink that we are doing this every week.(we are not doing this every week)
Nobodyneedknow the name of the person who made the complaint.
Not a thingneedchange on this page.
Needcomes first in the verb phrase (after the subject and before another verb):
Let’s forget about it. No oneneedknow about it.
We can’t use another modal verb withneed:
No oneneedread this.
Not:No one need must read this. orNo one must need read this.
Negative form
We form the negative by addingnotafterneed.Need notcan be contracted toneedn’t. We don’t usedon’t/doesn’t/didn’twith the semi-modal verbneed:
Youneed notspend a lot of money on presents.(formal) (orYou needn’t spend a lot of money on presents.)
Not:You don’t need spend a lot of money on presents.
See also:
Modal verbs
Semi-modalneedand main verbneed
Question form
The question form of the semi-modalneedis not very common. It is rather formal. The subject andneedchange position to form questions. We don’t usedo/does/did.
Needwe write this down?
Not:Do we need write this down?
Need: use
No obligation (needn’t)
The semi-modalneedis most common in the negative. We use it to show that there is no obligation:
Weneedn’tspend much time on this topic. It’s not going to be in the exam.
Cans of soupneedn’tbe kept in the fridge.
No obligation in the past
The semi-modalneedhas no past simple form. Instead, we usedidn’t need toordidn’t have towhen we express no obligation in the past:
Ididn’t need tobuy any books. They were all in the library.(main verbneed+to)
(orIdidn’t have tobuy any books. They were all in the library.)
Not:I didn’t need buy any books. They were all in the library.
See also:
Semi-modalneedand main verbneed
Unnecessary events
We useneedn’t have + -edform to refer to events which happened but which the speaker considers were unnecessary:
Youneedn’t have waitedfor me.(You waited for me but it wasn’t necessary.)
Youneedn’t have boughtso much food. There are only three of us staying for the weekend.(You bought a lot of food but it wasn’t necessary.)
Semi-modalneedand main verbneed
We can use main verbneedas an alternative to semi-modalneed. Main verbneedis followed bytoand it changes with person, number and tense (I, you, we, they need to; she, he, it needs to; I, you, she, he, it, we, they needed to).
Semi-modalneed | Main verbneed | Comment |
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| In these examples, the meaning is the same for semi-modalneedand main verbneed + to. |
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We must use the main verbneedwhen it is followed by a noun phrase or -ingclause:
Youdon’t need[noun phrase]an umbrella.
Not:You needn’t an umbrella.
My hairdoesn’t need[-ing clause]cutting for at least another month.
Not:My hair needn’t cutting for at least another month.
Typical error
The mainverbneedis followed bytowhen used with another verb.
Ineed tohave my hair cut.
Not:I need have my hair cut.