who or whom? Grammatically, who and whom are the subject and object forms respectively of the same word: Who wrote the letter, and to whom was it addressed?. Who corresponds to I, he, she or they; whom corresponds to me, him, her or them: They saw whom? –They saw him. Whom, however, is being increasingly relegated to very formal use in modern English, except after prepositions especially in questions: Whom have I the honour of addressing?, but Who were you speaking to just then? or Who did you see at the meeting? The same is largely true for the use of whom as a relative pronoun. Many people would argue that if the man who I saw yesterday is grammatically incorrect, the man whom I saw yesterday sounds pedantic, and it is therefore better to say the man that I saw yesterday or, simply, the man I saw yesterday. See also note at that⁴