Adjectival agreement

Agreement or concord (abbreviated agr) happens when a word changes form depending on the other words to which it relates. It is an instance of inflection, and usually involves making the value of some grammatical category (such as gender or person) "agree" between varied words or parts of the sentence.

For example, in Standard English, one may say I am or he is, but not "I is" or "he am". This is because the grammar of the language requires that the verb and its subject agree in person. The pronouns I and he are first and third person respectively, as are the verb forms am and is. The verb form must be selected so that it has the same person as the subject.

The agreement based on overt grammatical categories as above is formal agreement, in contrast to notional agreement, which is based on meaning. For instance, in American English the phrase The United Nations is treated as singular for purposes of agreement even though it is formally plural.

Agreement generally involves matching the value of some grammatical category between different constituents of a sentence (or sometimes between sentences, as in some cases where a pronoun is required to agree with its antecedent or referent). Some categories that commonly trigger grammatical agreement are noted below.

Agreement based on grammatical person is found mostly between verb and subject. An example from English (I am vs. he is) has been given in the introduction to this article.

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