Once students learns about the different forms and tenses of verbs, the next step is learning about number agreement between the verb and its subject. This Turtle Diary lesson explains about subject-verb agreement. If the subject is plural the student must use a plural form of the verb. Likewise, a singular subject requires a singular form of a verb. There are exceptions to the rule though and the lesson explains about indefinite pronouns and compound subjects. This is an important lesson as understanding the use of verbs is a major part of language arts skills.