Concord means agreement, and the rules of grammatical concord are the principles of agreement between words in the sentence. The two major forms of grammatical concord and the most rigorously applied in written English are:
Subject – Verb Agreement.
Pronoun – Antecedent Agreement.
(A) SUBJECT-VERB AGREEMENT
This refers to the agreement (harmonious relationship) between a finite verb and its subject, but never its object, in number and person. A singular verb (SV) agrees with a singular subject (SS) while a plural verb (PV) agrees with a plural subject (PS):
Chinwe goes to school. (SS+SV)
Chinwe and Ebele go to school. (PS+PV)
Recognising Number and Person in Subject-Verb Agreement
To understand subject-verb agreement, one should be able to recognise a singular subject and a singular verb or a plural subject and a plural verb. If the subject consists of a single or compound noun (as in A (I) and (ii) above), agreement is easy to determine. But where the subject is a complex noun phrase, the head noun in the nominal group must be located first before matching the correct verb with it. Consider the head nouns in the following complex noun phrases and see how they agree with their verbs:
The dream of snakes upsets Amaka.
The thought of girls disturbs Obika.
A number of workers have gone.
The number of workers has reduced drastically.
One of our brothers sings sweet songs.
The products of modern science are useful.
Indiscipline among teachers has destroyed education.
The influence of students in the party pains us.
Some additional parts like the tail are needed.
The ugly old girl picking stones there is enterprising.
Agreement, Tense and the Verb
It is pertinent to note that agreement is realised only in the present or present perfect tense but never in the past tense. Also noteworthy is the fact that most verbs in the present tense have S form (upsets, disturbs, has, sings, is) for the third person singular subject only. Other persons (1st and 2nd person singular and 1st, 2nd and 3rd person plural subjects) take the infinitive or base form of the verb to agree in the present tense. Note also that the person of the verb is determined by the person of the subject. It is wrong to say that the “-S form” of the verb is plural; it cannot agree with ? plural subject, and verbs do not form their plural by the addition of ‘S’ like nouns. Rather, a verb agrees with the number (i.e. it assumes the number) of its subject, thus obeying the subject verb agreement rule that:
1) If the subject of a verb is singular in number, the verb must also be singular:
Ezinne loves her husband. (SS + SV).
2) If the subject of a verb is plural, the verb must be plural too:
Ijeoma and Georgina are good girls. (PS+PV)
The following are further illustrations of the application of this rule (subject-verb agreement) with different types of subjects:
3) A verb must agree with its subject and not with the complement:
The three men’s only guide was the stars. (SS+SV)
4) If the subject is a substantive (an adjective-noun: adjective used as noun) denoting number of persons or things, its verb must be plural:
The rich also cry. (PS+PV)
The poor in spirit are blessed. (PS+PV)
5) If the subject is a relative pronoun, the verb should agree with the antecedent of the relative pronoun:
We know the girl who has eaten your food. (SS+SV)
6) If the subject is a verbal (e.g. an infinitive or a gerund/verbal noun) or a noun clause, the verb must be singular:
To work is to pray. (Infinitive: SS+SV)
Singing is my hobby. (Gerund : SS+SV)
Excessive swinging of the arm is dangerous. (verbal noun:SS+SV)
What he did is an abomination. (noun clause: SS+SV)
7) A collective noun takes a singular verb:
The committee has resolved to work harder (SS +SV)
The Council is sitting now. (SS+SV)
8) But a noun of multitude (i.e. a collective noun viewed from the perspective of the individual members) takes a plural verb:
The Council have amended the edict. (PS+PV)
9) Titles of books and names of organisations (associations) require singular verbs:
Things Fall Apart is Achebe’s best novel.
Sons and Lovers has a rich moral depth.
10) If singular subjects are joined by and, the verb must be plural:
Ikechi and Mbachu are close friends (PS+PV)
11) If singular subjects are separated by or, either …. or, nor, or neither … nor, the verb must be singular:
Neither you nor I am wrong.
12) If a plural subject denotes a particular amount or quantity regarded as a single unit, the verb is singular:
Fifty miles is a long distance.
Eighty-five years/litres is enough.
13) Nouns that end in -ics and denote fields of study take singular verbs (e.g. Economics, Linguistics, Mathematics, Physics):
Statistics is not harder than Mathematics.
14) Singular subjects joined by as well as, with, in addition to, together with, in the company of, along with or accompanied by take singular verbs:
The man as well as his wife has gone.
15) But if one of the two subjects is plural, the verb agrees with the former of the two subjects:
The Governor as well as his entourage has come.
The girls together with their father have left.
16) If singular subjects joined by and are introduced by each or every, the verb must be singular:
Each boy and each girl has been flogged.
Every door and window has been locked.
17) Names of diseases that end in s are singular and should take singular verbs:
Measles is a contagious disease.
18) If a sentence begins with There/Here, the verb agrees with the headnoun after it:
There is a man in the room.
There are men in the room.
19) Similarly, if an auxiliary verb introduces a direct question, the subject comes after the auxiliary verb:
Has Ngozi eaten?
Are the boys ready to work?
20) The number and many a take singular verbs but a number and a great many take plural verbs:
The number of boys (that came here) is unknown.
A number of boys (that came here) have gone.
Many a man knows her name.
A great many men know her name.
B) PRONOUN-ANTECEDENT AGREEMENT
The pronoun must agree with its antecedent in number, gender, and person but not in case. (Note: For pedagogical convenience, possessive adjectives derived from pronouns are here referred to as “pronouns”, for they express the number, person and gender of the antecedents to which they refer.) The antecedent of a pronoun is any preceding noun or nominal to which the pronoun refers. Example: Ngozi gave us her pen; John gave us his book (Here, the pronoun “her’ refers to Ngozi while “his’ refers to the noun John).
Agreement in Number
The agreement in number between a pronoun and its antecedent states that if the antecedent is singular, the pronoun must be singular; and, if the antecedent is plural, the pronoun referring to it must also be plural. Consider the following:
The students love their English teacher (plural antecedent + plural pronoun).
Obi and Ada did their assignments timely. (PA+PP)
The Registrar and Secretary of the University knows his job. (SA = SP).
The Registrar and the Secretary of the Organisation hold their views. (PA+PP).
Each boy and each girl must do his or her best. (SA +SP).
Every man and every woman should air his/her views. (SA+SP).
Either Ngozi or her sister ate her food. (SA +SP).
Neither Ngozi nor her sisters ate their food. (PA=PP).
The age grade (a group of people) has postponed its meeting. (SA +SP).
The committee has/have rescinded its/their decision. (SA+SP/PA+PP).
Ebere is one of the girls who love their parents. (PA +PP)
Those who came late paid their fines. (PA +PP)
From the foregoing, the following rules can be deduced:
If an antecedent is made up of two or more singular nouns joined by and, the pronoun referring to it must be plural.
If the two singular nouns joined by and refer to one and the same person, the pronoun referring to them must be singular, but if the two singular nouns joined by and refer to different persons, the pronoun referring to them must be plural.
If each of the ‘conjoins’ (co-ordinated units) is introduced by each or every, the pronoun referring to them is singular.
If the singular conjoins are connected by or, either ……. or, or neither ……. nor, the pronoun referring to them must be singular, but if one of the `conjoins’ is plural, the pronoun referring to them must be plural.
The pronoun referring to a collective noun must be singular while that referring to a noun of multitude must be plural.
The pronoun whose antecedent is a relative pronoun agrees in number with the noun preceding the relative pronoun.
Note that even though a relative pronoun agrees in number with its antecedent, its case is usually nominative while the case of its antecedent is usually objective.
Agreement in Gender
A pronoun agrees with its antecedent in gender when it reflects the gender of its antecedent; that is, if the antecedent is masculine, the pronoun referring to it must be masculine; if the antecedent is feminine, the pronoun referring to it must be feminine; if the antecedent is neuter (or collective), the pronoun referring to it must be in the neuter gender; and, if the antecedent is common gender (e.g. cousin, child), the pronoun referring to it must identify the inherent gender (e.g. My cousin gave me her word or My cousin gave me his word). Use he when the gender of the antecedent is not known to be male or female (e.g. Who is knocking? Let him in.)
Agreement in Person
The agreement in person between a pronoun and its antecedent shows that a pronoun must be in the first person if its antecedent is in the first person, or in the second person if its antecedent is in the second person, or in the third person if its antecedent is in the third person:
I have my reasons.
You know your reasons.
They gave their reasons.
It must be noted, however, that a pronoun should be in the first person plural if the antecedents it refers to are of different persons including the first person e.g. You, James, and I did our assignments. Notably, when the antecedent is made up of different persons occurring together, the usual order is that the second person comes first (you) followed by the third person (He/She/it), and the first person comes last (I/we) as exemplified above.
(C) OTHER RULES OF CONCORD
Other rules of concord are:
1) Adjective – Noun concord
A singular noun agrees with a singular demonstrative adjective while a plural noun agrees with a plural demonstrative adjective:
This girl is thin but that one is fat(singular).
These pupils are obedient but those students are not (plural).
2) Subject – Complement Concord
If the, subject is singular, its complement must be singular; but if the subject is plural, its complement must be plural:
Jude is a lawyer but his wife is a nurse. (Singular)
Okeke and Okafor are Igbo names (Plural)
3) Subject – Object Concord
This refers to the agreement between the object and its subject (in number, person and gender) where the object is a reflective pronoun:
Obinna hurt himself. (Singular)
The students betrayed themselves. (Plural)
4) Object – Object Complement Concord
This is the agreement in number between an object and its complement in a sentence:
We elected Mr. Steve Chairman. (singular)
The Principal called the boys scapegoats. (plural)
5) Verb – Verb Concord
This refers to logical tense sequence between verbs within clauses in any sentence:
She left when her husband entered the room.
If you were there, you would see him.
6) Proximity Concord
If two nominatives are separated by either … or or neither … nor, the verb agrees with the nominative that immediately precedes it:
Either Emma or Ifeanyi knows the way.
Neither you nor I am worried.
Either the boy or his friends were invited.
Either his friends or the boy was invited.
This refers to the wrong kind of concord which, though found in spoken English and some informal expressions, is considered grammatically unsound. Two common types of this aberrant concord are notional concord and pseudo-proximity concord:
(i) Notional Concord
This is matching possessive adjectives with verbs or matching one’s notion of the subject number with the verb instead of identifying and matching the real number of the nominative with the verb:
Notional Concord (Wrong)
Enugu and Nsukka honey taste so good.
Everybody have eaten their food.
Grammatical Concord (Right)
Enugu and Nsukka honey tastes so good.
Everybody has eaten his food.
(ii) Pseudo – Proximity Concord (unacceptable)
This refers to the ungrammatical matching of the verb with its preceding noun, regardless of the standard operating principles of subject – verb agreement.
Pseudo – (ungrammatical) proximity Concord (Wrong)
None of the tumblers are in the cupboard.
One of my friends have arrived.
Nobody but his sisters love him.
Real (grammatical) Concord (Correct)
None of the tumblers is in the cupboard.
One of my friends has arrived.
Nobody but his sisters loves him. (i.e. Nobody loves him except his sisters