Singular is when the word is referred to just one person, one physical object or one objective.
For example:
Boat, Sword, Hill, Dog, Log
Boy, You, I, She, He
They all refer to just one thing or one person.
Plural is when the word refers to multiple people, multiple physical objects or multiple objectives
Lovers, Swords, Hills, Creams, Drinks
They, We,Them
These words refer to a reader that there is more than one person or objects found in a situation or environment.