Q: Which is correct, “who” or “whom,” in the following sentence? “It involves all girls, of all races and backgrounds, many of who/whom are held back by societal barriers.”
A: It should be “whom.” The clause at the end of that sentence should read “ … many of whom are held back by societal barriers.”
As you know, a clause has its own subject and verb. In this clause, the subject is “many,” and the verb is “are.”
Don’t be misled by “of whom” in phrases like “many of whom,” “several of whom,” “most of whom,” “all of whom,” “few of whom,” “one of whom,” and so on.
The subject in such a phrase is what precedes “of.” The prepositional phrase beginning with “of” merely modifies the subject.
Grammarians say that in phrases like these, a word such as “some” or “many” is a quantifier; it expresses quantity. And the prepositional phrase “of whom” functions as a partitive; it hints at the whole of which only a part is being referred to.
The Cambridge Grammar of the English Language gives several examples of this kind of “preposition + whom” construction: “some of whom, all/both/many/few/none/two of whom, etc.”
In his book Essentials of English Grammar, Otto Jespersen illustrates the partitive use of the preposition “of” with these examples: “He had two daughters, both of whom were married. … He had two daughters, one of whom married a judge.”
A simpler way to look at all this might be to compare a similar clause: “Many of them are held back by societal barriers.”
Here too, the subject is “many,” and the prepositional phrase “of them” is a partitive.
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