Learn English – Usage of “From” and “Of”

In spoken English, object pronouns are also used as emphatic or referential pronouns.

For example, I typically think of myself as "me," and a group including me as "us." We use these emphatic or referential pronouns in any stand-alone statement (i.e. one without a verb), such as a quick answer to a question.

Thus "who wants to come?" You could say in response "Me." "Us." "Not us." or "Her" or "Not us, but maybe them." (note that with "you" there is no ambiguity since the subject and object pronouns are the same.) Saying "I" or "we" or "they" or "she" is ungrammatical. Saying "I do" or "they don't" is fine but is not what most English speakers would do.

In prescriptive grammar, this is frowned upon. Hence, for instance, you can find scorepads for card games labeled "we" and "they." In my opinion this style of speech sounds very unnatural. Unless you are writing a formal document, you should aim to talk like the child in the movie, if your goal is to sound more like a native speaker.

Similarly, in response to "Who's there?" "That's me." Or when a stranger calls you on the phone and asks "Is Sarah there?" If you are Sarah, you say "that's me." (Prescriptivists will tell you to say "this is she," but this again sounds extremely formal.)

1. Such does indeed act as a pronoun, and its antecedent is indeed young men of four thousand a year.

2. Anaphora—the co-referential relationship between a pronoun and its antecedent— does not to my mind imply that the antecedent is present in the ‘deep structure’ of the utterance in which the pronoun is employed. There may be grammars which represent a pronoun-in-use as a ‘reduction’ of its antecedent, taken to be ‘present’ in a governing ‘deep structure’. This sort of analysis seems to me to contradict the facts of utterance and interpretation, and to be in consequence of very little value to the users of language, however sophisticated. Moreover, it sets the linguist on a slippery slope toward a philosophical monism in which the ultimate ‘deep structure’ is the entire language—and possibly also an experienced universe taken to be coterminous if not indeed identical with the language.

3. It is impossible to say that one or the other of these expressions is always preferable to the other, without regard to context; but it seems to me that of great wealth is not a ‘reduction’ but the ‘base’ form, and that the explicit relative who is of great wealth is an expansion of it which might be elicited in unusual circumstances.

I am not competent to address the further issues raised in your third question.