In the types of English in which "whom" is used (which are generally the more formal varieties, as described in the section above), the general grammatical rule is that "who" is the subjective (nominative) form, analogous to the personal pronouns "I", "he", "she", "we", "they", while "whom" is the objective (oblique) form, analogous to "me", "him", "her", "us" and "them". Thus, "who" is used as a verb subject, while "whom" is used as an indirect or direct object of a verb or as the object (complement) of a preposition.