Agreement or concord 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 different 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, the phrase The United States is treated as singular for purposes of agreement, even though it is formally plural.
By category 
Agreement generally involves matching the value of some grammatical category between different constitutents 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 between pronoun (or corresponding possessive adjective) and antecedent also requires the selection of the correct person. For example, if the antecedent is the first person noun phrase Mary and I, then a first person pronoun (we/us/our) is required; however most noun phrases (the dog, my cats, Jack and Jill, etc.) are third person, and are replaced by a third person pronoun (he/she/it/they etc.).
Agreement based on grammatical number can occur between verb and subject, as in the case of grammatical person discussed above. In fact the two categories are often conflated within verb conjugation patterns: there are specific verb forms for first person singular, second person plural and so on. Some examples:
- I really am (1st pers. singular) vs. We really are (1st pers. plural)
- The boy sings (3rd pers. singular) vs. The boys sing (3rd pers. plural)
Again as with person, there is agreement in number between pronouns (or their corresponding possessives) and antecedents:
- The girl did her job vs. The girls did their job
Agreement also occurs between nouns and their modifiers, in some situations. This is common in languages such as French, where articles, determiners and adjectives (both attributive and predicative) agree in number with the nouns they qualify:
- le grand homme ("the great man") vs. les grands hommes ("the great men")
In English this is not such a common feature, although there are certain determiners that occur specifically with singular or plural nouns only:
- One big car vs. Two big cars
- Much great work vs. Many great works
- le grand homme ("the big man"; homme is masculine) vs. la grande chaise ("the big chair"; chaise is feminine)
Such agreement is also found with predicate adjectives: l'homme est grand ("the man is big") vs. la chaise est grande ("the chair is big"). (However in some languages, such as German, this is not the case; only attributive modifiers show agreement.)
In the case of verbs, gender agreement is less common, although it may still occur. For example, in the French compound past tense, the past participle agrees in certain circumstances with the subject or with an object (see passé composé for details). In Russian and most other Slavic languages, the form of the past tense agrees in gender with the subject.
There is also agreement in gender between pronouns and antecedents. Examples of this can be found in English (although English pronouns principally follow natural gender rather than grammatical gender):
- The man reached his destination vs. The ship reached her/its destination
For more detail see Gender in English.
- der gute Mann ("the good man", nominative case) vs. des guten Mann(e)s ("of the good man", genitive case)
- Who came first – he or his brother? vs. Whom did you see – him or his brother?
By language 
Languages can have no conventional agreement whatsoever, as in Japanese or Malay; barely any, as in English; a small amount, as in spoken French; a moderate amount, as in Greek or Latin; or a large amount, as in Swahili.
Modern English does not have a particularly large amount of agreement, although it is present.
All regular verbs (and nearly all irregular ones) in English agree in the third-person singular of the present indicative by adding a suffix of either -s or -es. The latter is generally used after stems ending in the sibilants sh, ch, ss or zz (e.g. he rushes, it lurches, she amasses, it buzzes.)
Present tense of to love:
|First||I love||we love|
|Second||you love||you love|
|Third||he/she/it loves||they love|
There are not many irregularities in this formation:
- to have, to go and to do render has, goes and does.
The highly irregular verb to be is the only verb with more agreement than this in the present tense.
Present tense of to be:
|First||I am||we are|
|Second||you are||you are|
|Third||he/she/it is||they are|
Future tense of "to be":
|First||I shall be||we shall be|
|Second||you will be||you will be|
|Third||he/she/it will be||they will be|
Emphatic future tense of "to be":
|First||I will be||we will be|
|Second||you shall be||you shall be|
|Third||he/she/it shall be||they shall be|
Note: the use of shall and the use of the emphatic tense are rare in Standard English.
In Early Modern English agreement existed for the second person singular of all verbs in the present tense, as well as in the past tense of some common verbs. This was usually in the form -est, but -st and -t also occurred. Note that this does not affect the endings for other persons and numbers.
Example present tense forms: thou wilt, thou shalt, thou art, thou hast, thou canst. Example past tense forms: thou wouldst, thou shouldst, thou wast, thou hadst, thou couldst
Note also the agreement shown by to be even in the subjunctive mood.
Imperfect subjunctive of to be in Early modern English:
|First||(if) I were||(if) we were|
|Second||(if) thou wert||(if) you were|
|Third||(if) he/she/it were||(if) they were|
Compared with English, Latin (and Romance languages like Spanish and Italian) is an example of a highly inflected language. The consequences for agreement are thus:
Verbs must agree in person and number, and sometimes in gender, with their subjects. Articles and adjectives must agree in case, number and gender with the nouns they modify.
Sample Latin (Spanish) verb: the present indicative active of portare (llevar), to carry:
- porto (llevo) - I carry
- portas (llevas) - you [singular] carry
- portat (lleva)) - he carries
- portamus (llevamos) - we carry
- portatis (llevais) - you [plural] carry
- portant, (llevan) - they carry
Note also that the inflectional endings mean it is not necessary to include the subject pronoun, except for emphasis, or to avoid ambiguity in complex sentences. For this reason, Latin is described as a null-subject language.
Spoken French always distinguishes the first person plural and the second person plural from each other and from the rest of the present tense in all verbs in the first conjugation (infinitives in -er) other than "aller". In most verbs from the other conjugations, each person in the plural can be distinguished among themselves and from the singular forms. The other endings that appear in written French (i.e.: all singular endings, and also the third person plural of verbs other than those with infinitives in -er) are often pronounced the same, except in liaison contexts. Irregular verbs such as être, faire, aller, and avoir possess more distinctly pronounced agreement forms than regular verbs.
An example of this is the verb "travailler", which goes as follows (the forms in bold type sound /travaj/):
- je travaille
- tu travailles
- il travaille
- nous travaillons
- vous travaillez
- ils travaillent
On the other hand, a verb like "partir" has:
- je pars
- tu pars
- il part
- nous partons
- vous partez
- ils partent
Again, the forms in bold type sound alike (the final S or T is silent), and the other three forms sound differently from one another and from the singular forms.
However in liaison contexts, the final consonant is pronounced, helping differentiate at least "part" from "pars".
Adjectives agree in gender and number with the nouns they modify in French. As with verbs, forms that are written with different agreement suffixes are sometimes pronounced the same (e.g. joli, jolie), although in many cases the final consonant is pronounced in feminine forms, but silent in masculine forms (e.g. petit vs. petite). Most plural forms end in -s, but this consonant is only pronounced in liaison contexts, and it is determinants that help understand if the singular or plural is meant. The participles of verbs agree in gender and number with the subject or object in some instances.
Articles, possessives and other determinants also decline for number and (only in the singular) for gender, with plural determinants being the same for both genders. This normally produces three forms: one for masculine singular nouns, one for feminine singular nouns, and another for plural nouns of either gender:
- Definite article: le, la, les
- Indefinite article: un, une, des
- Partitive article: du, de la, des
- Possessives (for the first person singular): mon, ma, mes
- Demonstratives: ce, cette, ces
Notice that some of the above also change (in the singular) if the following word begins with a vowel: le and la become l′, du and de la become de l′, ma becomes mon (as if the noun were masculine) and ce becomes cet.
In Hungarian, verbs have polypersonal agreement, which means they agree with more than one of the verb's arguments: not only its subject but also its (accusative) object. Difference is made between the case when there is a definite object and the case when the object is indefinite or there is no object at all. (The adverbs do not affect the form of the verb.) Examples: Szeretek (I love somebody or something unspecified), szeretem (I love him, her, it, or them, specifically), szeretlek (I love you); szeret (he loves me, us, you, someone, or something unspecified), szereti (he loves her, him, it, or them specifically). Of course, nouns or pronouns may specify the exact object. In short, there is agreement between a verb and the person and number of its subject and the specificity of its object (which often refers to the person more or less exactly).
The predicate agrees in number with the subject and if it is copulative (i.e., it consists of a noun/adjective and a linking verb), both parts agree in number with the subject. For example: A könyvek érdekesek voltak "The books were interesting" ("a": the, "könyv": book, "érdekes": interesting, "voltak": were): the plural is marked on the subject as well as both the adjectival and the copulative part of the predicate.
Within noun phrases, adjectives do not show agreement with the noun, e.g. a szép könyveitekkel "with your nice books" ("szép": nice): the suffixes of the plural, the possessive "your" and the case marking "with" are only marked on the noun.
Slavic languages 
Most Slavic languages are highly inflected, except for Bulgarian and Macedonian. The agreement is similar to Latin, for instance between adjectives and nouns in gender, number, case and animacy (if counted as a separate category). The following examples are from Serbian:
- živim u malom stanu "I live in a small apartment" (masculine inanimate, singular, locative)
- živim u maloj kući "I live in a small house" (feminine, singular, locative)
- imam mali stan "I have a small apartment" (masculine inanimate, singular, accusative)
- imam malu kuću "I have a small house" (feminine, singular, accusative)
- imam malog psa "I have a small dog" (masculine animate, singular, accusative)
Verbs have 6 different forms in the present tense, for three persons in singular and plural. As in Latin, subject is frequently dropped.
Another characteristics is agreement in participles, which have different forms for different genders:
- ja sam jela "I was eating" (female speaking)
- ja sam jeo "I was eating" (male speaking)
Swahili, like all other Bantu languages, has numerous noun classes. Verbs must agree in class with their subjects and objects, and adjectives with the nouns that they qualify. For example: Kitabu kimoja kitatosha (One book will be enough), Mchungwa mmoja utatosha (One orange-tree will be enough), Chungwa moja litatosha (One orange will be enough).
There is also agreement in number. For example: Vitabu viwili vitatosha (Two books will be enough), Michungwa miwili itatosha (Two orange-trees will be enough), Machungwa mawili yatatosha (Two oranges will be enough).
Class and number are indicated with prefixes (or sometimes their absence), which are not always the same for nouns, adjectives and verbs, as illustrated by the examples.
See also 
- Case government
- Redundancy (linguistics)
- Sequence of tenses — sometimes called agreement of tenses
- Synthetic language
- Algeo, Pyles (2009). The Origins and Development of the English Language. Cengage Learning. p. 4. ISBN 1428231455.
- Merriam-Webster (1998). Merriam-Webster's Manual For Writers And Editors. Merriam-Webster. p. 376. ISBN 087779622X.
- Cervel, Mendoza Ibáñez (2005). Cognitive Linguistics: Internal Dynamics and Interdisciplinary Interaction. De Gruyter. p. 378. ISBN 3110197715.
Further reading 
- Corbett, Greville (1994) "Agreement". In R.E. Asher (ed.), The Encyclopedia of Language and Linguistics. Oxford: Pergamon Press. 54–60.
- Corbett, Greville (2006) Agreement. Cambridge Textbooks in Linguistics. Cambridge: Cambridge University Press.
- Givon, Talmy (1984) Syntax. A Functional Typological Introduction. Vol 1. Amsterdam: John Benjamins. Chapter 10.
- Mel'čuk, Igor (2006): Aspects of the theory of morphology. Berlin, New York: Mouton de Gruyter. Chapter 1.
- Moravcsik, Edith A. (1978). "Agreement". In: Joseph Greenberg, (ed.), Universals of Human Language. vol. 4. Stanford: Stanford University Press, 331–374.