Raise your hand if you know how to use whom. Now keep it raised if you’re confident you can explain its use in the following sentence: “One would do well to ask whom that was and by what means the communication took place.”
Now keep it raised if — and only if — you figured out that this usage of “whom” is wrong.
My guess is no one’s deltoids are getting a workout right now.
As I’ve said in this space before, “whom” is usually more trouble than it’s worth. Just when you think you have it down, you can get it wrong.
And since the whole reason to use “whom” in the first place is to be proper, it doesn’t help when “whom” leads to errors.
When I talk about these pitfalls, I usually focus on sentences like “I’ll hire whomever I believe has the best qualifications.”
People think that the object of “hire” and should be an object pronoun, whomever.
But the object of “hire” is the whole clause, whose subject is “whoever” and whose verb is “has,” which is why that sentence should say “whoever has the best qualifications.”
The secret here: anytime you don’t know whether to use “whomever” or “whoever” in the middle of a sentence, look around and see if there are any verbs that need “whoever” to be their subject. “Has the best qualifications” needs a subject, so we use “whoever” here.
That’s advanced stuff, and it’s understandable why so few people get it right. But the “whom” in our first example is a whole other level of difficult.
To understand why it’s wrong, you don’t just need to know that “who” is a subject and “whom” is an object. You don’t just need to know that a clause can be the object of a verb. You need to know the term “predicate nominative.”
The predicate nominative is the reason people on the phone say “This is she” instead of “This is her.”
Normally, after a verb, we use an object pronoun. I saw her. But in “This is she,” we use a subject pronoun in a spot where we might normally expect to find an object like “her.”
The reason has to do with the special qualities of the verb “to be,” along with a handful of other verbs that express being and the like. “Be” doesn’t express action the way “see” does. Instead, it refers back to the subject.
In school, we learned about subjects and predicates. Almost as quickly, we learned that knowing about predicates isn’t very useful.
Most of the time, we use the term to mean the stuff in the sentence that comes after the subject — a concept that does little to help our writing.
But this is one case where the concept of predicates is useful: It helps us understand the term “predicate nominative,” which means that the subject, referred to by the word “nominative,” makes an appearance in the predicate: the “she” in “This is she.”
This is also why, technically, it’s proper to say stuff like “It is he who spoke” or “It was I” or “The culprit was she.” Obviously, no one expects you to talk like that.
But if you want to use formal language, you should probably get it right. In our example sentence, that requires spotting the predicate nominative.
Focus just on the clause “Ask whom that was.” Its predicate nominative situation is a little hard to see because the words are arranged to form a question. Instead of “that was whom,” it’s “whom that was.”
But the bones are the same. You have a subject, “that,” and a verb that’s a form of “be,” plus a pronoun that should be in subject form to create a predicate nominative: That was who.
So our original sentence should be “One would do well to ask who that was,” not whom. If the speaker hadn’t tried to be proper, she probably would have gotten it right without trying. But because she had an incomplete grasp of how to use “whom,” her efforts backfired.