To Be or Not To Be...the Predicate Nominative?

In English, there are verbs and then there is the "to be" verb—a copula—and the most irregular verb of all of the irregular verbs in the entire language. This is a verb that gives fits to native speakers. Its sheer ontology is fuddled by even the most educated of speakers around. It is a verb that creates its own set of rules and I shall explain how these rules work.

First, it's a copula, or a linking verb. There are a slue of linking verbs in English such as to become, to feel, to taste, to look, and so on. Now, these verbs listed are not arrant copulative verbs; they can be action verbs as well. It just depends on how they are used.

Now, in English, there are only a couple of copulas that can form a predicate nominative and one is the "to be" verb. Below is an example of the "to be" verb using the predicate nominative:

It is I [who am to blame.]

The subject of the sentence is bold (It), the copula is italicized (third person singular present indicative "to be"), and the predicate nominative or subject predicate is bold and incarnadined (I). The restrictive clause is started with the interrogatory pronoun, "who" and must correspond in conjugation of its verb with the word it is modifying, which is "I" in this sentence.

Here, many speakers would never construct this sentence correctly in both the predicate nominative part and the restrictive clause part. A native speaker would probably utter something like, "It's me who's to blame", but this is totally wrong under normative English grammar rules.

First off, "me" is the objective pronoun of "I" and needs to be a direct or indirect object of an action verb that it is modifying for it to be formed this way. "To be" is not an action verb; ergo "me" cannot modify it because it cannot have a direct object. "To be" is a copula that is linking the subject of the clause, "It" to its subject predicate, "I". The subjective interrogatory pronoun, "who" is modifying the predicate nominative, "I" so its verb conjugation must correlate with its modifier; thus the conjugation of first person singular present indicative "to be" is "am" so the syntagm is "who am" in this case.

"To be" is strange when it is in its infinitive state. It mimics what it modifies so that's how one knows what pronoun to use. If the infinitive have no subject, it will take a subjective pronoun; if it have a subject, it will modify its subject. Let me show some examples:

1. If anyone should win that prize, it is going to be I. (This could also say, "it will be I" or "it shall be I", but the main point to remember is that "to be" is modifying the subjective pronoun, "It" so it must have a subjective pronoun follow.)

2. I want the winner to be him. (Here, the subject of "to be" is modifying the direct object of the verb, "want"; therefore an objective pronoun must supervene.)

3. I was thought to be he. ("To be" has no subject here so it must be in the subjective form. If you invert the sentence, "He was thought to be I" means the exact same thing.)

4. They thought me to be him. (The subject of "to be" is "me" so this must match up; therefore an objective pronoun must be used. If you invert it, "They thought him to be me" means the same thing.)

I know that many people do not talk this way, but this is normative grammar at its finest and, to be blunt, all of these constructions can be avoided in formal writing so don't throw yourself in a pother over it. It's important that you know it, but you do not have to use it. This is supposed to be an exercise to help everyone understand how English works in this sense. I hope that this might have helped you a little bit. If you should have any questions, please feel free to ask.