Before you get information on plural pronoun usage, you need to understand the different types of pronouns and the way they are used in sentences.
The word “pronoun” comes from the Latin “pronomen” with “pro” meaning “in place of” and “nomen” meaning “noun, name.” A pronoun is a substitute for a noun. Our language would be too repetitive if you kept repeating a noun, so pronouns break up that repetition. Here are brief explanations of the kinds of pronouns and their usage.
Subjects and verbs have to agree according to whether they are singular or plural. The same is true of pronouns that act as subjects. Following are guides of plural pronoun usage according to the types of pronouns:
Now that you understand plural pronoun usage, you need to add to that knowledge how to make antecedents and pronouns agree. In some sentences, and even between two sentences, there is a pronoun that refers to a noun, pronoun, clause, or phrase that precedes it. The word, clause, or phrase that comes first is the antecedent and the pronoun has to agree with it.
Sounds easy enough, but there are some troublesome words when making pronouns and antecedents agree. With compound subjects, the agreement depends on the word that joins them. If “and” is used, then the pronoun must be plural. An example is: “Sue and Mary took their dogs to the park.” Since “and” is used, the subject us plural and the pronoun must also be plural. However, if the words “or” or “nor” are used, then the subject closest to the pronouns determines the agreement. For example, “The cat or the dogs like their treats.” Since “dogs” is plural, so is “their.”
Other problems can arise if there are several words or phrases between the pronoun and its antecedent. Sometimes, a pronoun’s antecedent is in the preceding sentence. In this case, just overlook the words between and that will help you determine the form needed.
Indefinite pronouns are the real troublemakers. These are singular and need singular pronouns: anyone, no one, everyone, someone, anybody, nobody, everybody, somebody, anything, everything, nothing, something, one, each, either, and neither. A word like “everyone” is treating people as a group, so it is singular. When using “either” or “neither”, it is one or the other, so you are looking at one at a time, so those two words are singular.
When the antecedent is an indefinite pronoun (some, none, all, most, or any) that is followed by a prepositional phrase, agreement depends on the type of object. If the object is countable, the pronoun will be plural. Here is an example, “ Most of the pennies fell out of their wrapper.” “Pennies” is plural, so “their” is plural. If the object is uncountable (like sugar, butter, air, money, or furniture), the pronoun needs to be singular.