Pronouns can cause problems when they don’t agree properly with the verb they take. There are two types of errors with pronouns.
For purposes of agreement, it is helpful to know which pronouns are singular and which are plural.
When a pronoun can be either singular or plural, check the noun it refers to. If the noun is countable, such as trees, books, or people, then the pronoun is plural. For exapmle, in the following sentence: Most of the trees in the park are deciduous.
If the pronoun refers to a noun that is not countable, such as energy, justice, or love, then the pronoun is singular. For exapmle: All of the energy leaves the room when Tina enters.
Some pronouns must refer to specific classes of objects. These pronouns are:
Pronoun referent errors typically occur when there is some ambiguity as to which noun the pronoun replaces. Which noun is the pronoun referring to in this sentence?
Many casual investors prefer certificates of deposit to risky stocks because they offer a more consistent return.
In the above sentence, the pronoun they may refer to certificates of deposit but, grammatically, the pronoun is ambiguous because risky stocks is also a plural noun to which the pronoun could possibly refer.