princessgillian says:
Forgive the typo(s) above. My typing isn't up to par.

bill_r says:
I haven't read the book yet, but judging from your table, N/P/O look like the "cases" of English: nominative, possessive, and objective.
"I saw her." =>
I = subject (nominative case)
her = object (objective case)
"That's my umbrella." =>
my = possessive form of 1st person singular pronoun.

German has one more case--the dative, corresponding in some cases to the indirect object function in English:
"I gave _her_ a present."
There is no difference between in the forms of direct and indirect object pronouns in _modern_ English (me, her, him, etc.) but in German they can be different, e.g., in the case of "I":
N: Ich, O: mich, D: mir, P: mein(etc.)
I wrote "O" for the German direct object's case but that may be wrong; it may actually be called something else; e.g., the "accusative" case in Russian is the case that generally corresponds to a direct object.

Hope this is of some help to you.

bill_r says:
Please forgive my "between in the forms", too; I meant "between the forms". Also, do you mean "their" (instead of "theirs") after "P:" in your table?