Is vs Are Subject Verb Agreement Today, we’re going to learn a little about subject-verb agreement Subject-Verb Agreement agreement (noun): in language, the form of one word being decided by the form of another word. Also known as "concord" In a sentence, the verb must agree in number with the subject. If the subject is singular, the verb must be singular. If the subject is plural, the verb must be plural. For example: singular He is American. plural They are American. Sometimes units can either be singular or plural The police are looking for someone.