Plural Nouns. You may know that a noun identifies a person, place, thing, or idea. A singular noun names one person, place, thing, or idea, while a plural noun names more than one person, place, thing, or idea. There are a few basic rules to remember when it comes to turning a singular noun into a plural noun. 1. Most singular nouns need an 's' at the end to become plural. These are the easy ones. You can just add an 's' to alien, taco, or skateboard, for example, and you instantly have aliens, tacos, and skateboards.