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English definition of “not”


adverb     /nɒt/ US  /nɑːt/
A1 used to form a negative phrase after verbs like "be", "can", "have", "will", "must", etc., usually used in the short form "n't" in speech : He's not fat ! I won't tell her. I can't go. Don't you like her? It isn't difficult (= it is easy ). I'm just not interested . He's not bad-looking (= he is quite attractive ). He's not as tall as his father .Yes, no and not A1 used to give the next word or group of words a negative meaning : I told you not to do that. I like most vegetables but not cabbage . "Come and play , Dad ." "Not now, Jamie." It was Yuko who said that, not Richard.Yes, no and not A2 used after verbs like "be afraid ", " hope ", " suspect ", etc. in short , negative replies : "Is he coming with us?" "I hope not." "Have you finished ?" "I'm afraid not."Yes, no and not if not A2 used to say what the situation will be if something does not happen : I hope to see you there but, if not, I'll call you.Yes, no and not or not A2 used to express the possibility that something might not happen : Are you going to reply or not? I still don't know whether she's coming or not.Yes, no and not humorous sometimes used at the end of a statement to show that you did not mean what you have said: That was the best meal I've ever had - not!Yes, no and not Grammar:No or not?No and not are the two most common words we use to indicate negation. We use no before a noun phrase:Grammar:NotNot is one of the most common words we use to indicate negation. It is often shortened to n’t and joined to an auxiliary verb or modal verb:Grammar:Not in negative statements (She hasn’t …, I did not …)We form negative declarative clauses with not after be (she is not talking), after modal verbs (they must not go) and after auxiliary verbs do and have (we did not like it; they have not eaten).Grammar:Not and n’t in questions (Did younot …? Wasn’t she …?)We use not or n’t to form negative questions:Grammar:Don’t, Do not: orders and instructionsWe use don’t + the base form of the verb or do + not + the base form of the verb to make negative imperatives. We use these to give orders, instructions or commands. Do not is stronger and much more formal:Grammar:Not: short repliesWe use not in negative short replies with mental process verbs (e.g. be afraid, guess, hope):Grammar:Not: contrastWe often use not after but to express a contrast. We often leave out the verb phrase or part of it in the second clause:Grammar:Not + -ing and not + toWe use not before an -ing clause in more formal styles:Grammar:Or notWe can use or not in questions to ask about a range of possibilities:Grammar:So and not with expect, hope, think, etc.We can use so after some verbs instead of repeating an object clause, especially in short answers. The verbs we do this with most are: appear, assume, be afraid (meaning ‘regret’), believe, expect, guess, hope, imagine, presume, reckon, seem, suppose, think:
(Definition of not adverb from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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