A noun or pronoun is of the first person when it denotes the speaker, as I, me, we, us, etc.:
A noun or pronoun is of the second person when it denotes the person or thing spoken to, as thou, thee, you, etc.
A noun or pronoun is of the third person when it denotes the person or thing spoken about, as he, him, she, it, they, etc.
When the sun rose, he darted his fierce beams
on the flowers, and they withered.
Pronouns and Number
Most pronouns, like nouns, have
separate forms to show whether they denote one person or thing, or more
than one. In other words, pronouns have number.
Again, the following pronouns by their form denote the plural number:
By their fruits ye shall know them.
The pronouns you, your, yours are used in both numbers.
In this sentence, it is easy to see that the pronouns denote the singular. But in the following sentence they denote the plural number.
Pronouns and Case
The pronouns in the table are in “nominative case.” They are pronouns that function as subjects or predicate nouns.
“Objective case” pronouns function as objects (indirect or direct) or as objects of prepositions.
Pronouns in “possessive case” can function as subjects, predicate nouns, or objects.
That book is yours. Mine is in my room. They forgot about theirs.
The pronoun “who” can be either singular or plural. It has an objective case form – “whom,” and a possessive case form "whose."