The correct answer to this question isBooks. Book is a singular word because it is referring to one. When a word is a plural, it is referring to more than one. Both singular and plural words are nouns, which is a person, place, or thing. Book is an example of a word that is easy to become plural.
This is because all that needed to be added as an "S" to the end of the word. Sometimes, making a word plural is hard. For example, when it comes to the word wife when the word becomes plural, the f must turn to a v and then an s is added to the end.
