Final answer:
The verb 'wants' in 'She wants' is a third-person singular verb because it matches the singular subject 'She.' Key factors in subject-verb agreement include whether the subjects are singular or plural, compound, or connected by conjunctions. Exceptions arise with compound subjects forming a single unit or with intervening words, but the subject's number always dictates the verb's form.
Step-by-step explanation:
In the sentence 'She wants,' the verb 'wants' is third-person singular to match the singular subject 'She.' Subject-verb agreement is important in English to ensure that the sentence is grammatically correct. Subjects always dictate the number and person of the verb; for instance, a singular subject takes a singular verb, and a plural subject requires a plural verb. Examples of subject-verb agreement can be seen in sentences such as 'Her watch and wallet were stolen' indicating that compound subjects joined by 'and' typically take a plural verb.
However, there are exceptions to this rule. When compound subjects are considered as a single idea or unit, or when they are joined by 'or' or 'nor', the singular or plural form of the verb depends on the subject closest to the verb, as in the sentences: 'Either your mother or your uncles remember' and 'Either your uncles or your mother remembers.' Additionally, singular verbs are used with indefinite pronouns and when intervening words or phrases appear between the subject and verb, the subject's number still dictates the verb's form.
Understanding the relationships between subjects, verbs, direct objects, indirect objects, linking verbs, and be verbs is essential in constructing grammatically correct English sentences.