Negative Sentences

A negative sentence states that something is not true, does not happen, or does not exist. The core mechanism in English is the word not, placed after an auxiliary verb.

Every negative sentence needs either not with a verb or a negative word like never, nothing, nobody. A sentence cannot become negative by simply dropping not in front of the main verb without an auxiliary.

Negating "be"

The verb be is the only verb that takes not directly, with no extra auxiliary.

With is not and are not, two contracted forms exist: she's not and she isn't mean exactly the same thing. With I am not, the only standard contraction is I'm not — the form amn't does not exist in standard English.

Negating with "do"

For all other verbs in the present simple and past simple, English adds the auxiliary do to carry not. The main verb returns to its base form.

This is where most mistakes happen. English does not allow I not like or she not works — the auxiliary do is required. And after doesn't or didn't, the main verb always stays in its base form: she doesn't like, not she doesn't likes; they didn't go, not they didn't went.

Negating other auxiliaries

Any auxiliary or modal verb takes not directly after it.

Notice that will not contracts to won't, not willn't. And cannot is written as one word in its full form, while the contraction is can't.

Contractions

In speech and informal writing, the contracted form is standard. The full form (do not, is not, will not) sounds formal and is mainly used in written documents, legal texts, or for emphasis.

When a speaker stresses not for emphasis, the full form may appear in speech too: I do NOT agree with that. But in everyday conversation, contractions are the default.

"No" vs "not"

Not attaches to verbs. No goes directly before a noun.

Both forms are correct. The no + noun version often sounds slightly stronger or more direct.

No before a noun works with any verb — including be, have, and others.

One important restriction: no cannot replace not with a verb. I no like this is not English — the correct form is I don't like this or I like nothing about this.

Negative words

Several words carry a negative meaning on their own, without needing not.

• never — at no time: He never eats breakfast.
• nothing — not anything: There is nothing in the box.
• nobody / no one — not any person: Nobody answered the phone.
• nowhere — not any place: The cat was nowhere in the house.

When a sentence uses one of these words, the verb stays positive — do not add not.

Each negative word has a positive counterpart used in not-sentences:

Both versions are correct. The choice is mostly a matter of emphasis and style.

Double negatives

In standard English, one negative per clause is the rule. Two negatives cancel each other out and create a positive meaning — or, more often, just sound wrong.

The correct versions:

This applies to all negative words. If not is already on the verb, use the positive counterpart of the negative word.

Double negatives are common in some dialects and in informal speech, but they are considered incorrect in standard written and spoken English. In formal or professional contexts, always use one negative per clause.

Negative questions (Don't you like coffee?) follow different rules and are covered separately.

Common mistakes

Missing auxiliary "do"

Past form after "didn't"

Third-person -s after "doesn't"

Using "didn't" with "be"

Double negatives