Affirmative and negative

In linguistics and grammar, affirmative and negative (abbreviated respectively AFF and NEG) are terms of opposite meaning which may be applied to statements, verb phrases, clauses, or other utterances. Essentially an affirmative (positive) form is used to express the validity or truth of a basic assertion, while a negative form expresses its falsity. Examples are the sentences "Jane is here" and "Jane is not here"; the first is affirmative, while the second is negative.

The grammatical category associated with affirmative and negative is called polarity. This means that a sentence, verb phrase, etc. may be said to have either affirmative or negative polarity (its polarity may be either affirmative or negative). Affirmative is typically the unmarked polarity, whereas a negative statement is marked in some way, whether by a negating word or particle such as English not, an affix such as Japanese -nai, or by other means, which reverses the meaning of the predicate. The process of converting affirmative to negative is called negation – the grammatical rules for negation vary from language to language, and a given language may have more than one method of doing so.

Affirmative and negative responses (especially, though not exclusively, to questions) are often expressed using particles or words such as yes and no, where yes is the affirmative and no the negative particle.

Special affirmative and negative words (particles) are often found in responses to questions, and sometimes to other assertions by way of agreement or disagreement. In English, these are yes and no respectively, in French oui, si and non, in Swedish ja, jo and nej, and so on. Not all languages make such common use of particles of this type; in some (such as Welsh) it is more common to repeat the verb or another part of the predicate, with or without negation accordingly.

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