Objective (grammar)
From Freepedia
An objective pronoun functions as the target of a verb, as distinguished from a subjective pronoun, which is the initiator of a verb. Objective pronouns are instances of the oblique case.
In English, many pronouns are different from their corresponding subjective pronouns: I/me, we/us, he/him, she/her, who/whom, and they/them.
English once had an extensive declension system that specified distinct pronouns for accusative and dative cases. This collapsed into a single pronoun for both accusative and dative cases, now called the objective pronoun. See declension in English.
Regional differences
Several relatively common usages of objective pronouns in the subject position are regarded as errors by prescriptive grammarians, though descriptive grammarians class such usages as dialect and a natural part of language evolution. Various dialects of English often disregard subjective/objective pronoun distinctions in certain cases.
For example, to use the objective pronoun in a compound subject is traditionally considered grammatically incorrect.
Incorrect: You and me are going to school together.
Correct: You and I are going to school together.
Correct: The teacher teaches you and me.
Also, using the objective pronoun for the second word in a comparison using the conjunction than is traditionally considered incorrect if a subjective pronoun would be necessary in the "full" form of the sentence. This rule is very often disregarded in many varieties of English, to the point where a sentence constructed using "proper" grammar can, in some cases, be perceived as artificial or archaic to a native speaker.
Incorrect: You are a better swimmer than her.
Correct: You are a better swimmer than she. (You are a better swimmer than she [is].)
Correct: They like you more than her. (They like you more than [they like] her.)
Following a copula (linking verb) with an objective pronoun is traditionally considered incorrect, following the logic that, as the subject and the object are the same, they should share the same case. Again, to some ears the first "correct" sentence below sounds artificial and awkward.
Incorrect: The winner was me.
Correct: The winner was I.
Correct: I was the winner.
Finally, the word whom, technically the objective form of who, is falling into disuse in some areas. Who is commonly being used for both the objective and nominative cases, similar to the word you.
Incorrect: Who should I tell?
Correct: Whom should I tell?
Correct: Who should hear that?
It should be restated that labelling these differences "correct" and "incorrect" is a prescriptive response to dialectical differences from standard written English.
