(8) An interjection is a cry expressing emotion, but not forming part of the sentence.
NOUNS
+21. Classes of Nouns.+—Nouns are divided into two general classes: proper nouns [Esther] and common nouns [girl].
Common nouns include abstract nouns [happiness] and collective nouns [army].
Any word mentioned merely as a word is a noun: [And is a conjunction].
+22. Inflection.+—A change in the form of a word to denote a change in its meaning is termed inflection.
+23. Number.+—The most common inflection of the noun is that which shows us whether the name denotes one or more than one. The power of the noun to denote one or more than one is termed number. A noun that denotes but one object is singular in number. A noun that denotes more than one object is plural in number.
The plural number of nouns is regularly formed by adding s and es to the singular [bank, banks; box, boxes].
Other points to be noted concerning the plural of nouns are as follows:—
1. The irregular plural in en [child, children].