Personal Pronouns Have Number,Person And What?

Answer 1

As has been mentioned, personal pronouns in English are marked by FOUR things:
person, number, gender, case

BUT not all forms are marked for all of them. Rather:

* ALL pronouns distinguish "person" =1st, 2nd or 3rd
e.g., 1st - I, we; 2nd - you; 3rd - he, they

* All FIRST & THIRD person pronouns distinguish "number" =singular vs. plural
e.g. 1st - I vs. we
3rd - he (she, it) vs. they

(archaic forms of the 2nd person also distinguish -
'thou' vs. 'ye'/ 'thee' vs. 'you')

*MOST FIRST & THIRD person prouns distinguish "case"
-- subject ('nominative')/object ('accusative') = I/me, we/us, he

+ possessive ('genitive') pronouns - my, our, his, her, their
... mine, ours, his, hers, its, theirs

* 2nd person pronouns also distinguish case for the possessive form "yours"

* ONLY 3rd person SINGULAR distinguishes GENDER, and even that not in all cases of the neuter:
(gender - subject/object/possessives)
masculine - he/him/his, his
feminine - she/her/her, hers
neuter - it/it/its

Answer 2

Case

Pronouns change for case - in other words, whether they are the subject or the object. They also change if they are possessive.

Answer 3

Case and gender.

Answer 4

person
number
gender and
case