Affirmation and negation

Grammatical category indicating truth or falsehood

In linguistics and grammar, affirmation (abbreviated aff) and negation (neg) are ways in which grammar encodes positive and negative polarity into verb phrases, clauses, or utterances. An affirmative (positive) form is used to express the validity or truth of a basic assertion, while a negative form expresses its falsity. For example, the affirmative sentence "Joe is here" asserts that it is true that Joe is currently located near the speaker.

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