One of the great frustrations most of us have when we try to learn a new skill or improve on an old one is being told that we can do better, but not being told how. Friends or colleagues who look at our writing, for example, might with the best of intentions tell us, I don’t know, this sentence just doesn’t work, or even less helpfully say, You need a comma here, neglecting all the while to tell us exactly why.
Knowing the reasons behind the rules is the bedrock on which to raise a defense for studying the theory of anything we’d like to learn how to do. Practice and theory are two pillars of the skill we’re trying to build, and the third and fourth are practice and practice again. But without theory—or call it principles or rules or standards—we have no way of knowing how far we can rightfully depart from the norm and still communicate our thoughts clearly and compellingly. Think of theory as the knowledge that helps us put our thoughts in the best shape possible, fit and conditioned to communicate what we have to say.
Take, for example, this sentence (and you can assume a medical or political context as you wish): What I realized was it was going to take a long time to heal. That should sound a little awkward to our better literary ears: the sentence begins with the pronoun what, pointing our attention to something and leading us to expect a noun, but then veers in the direction of a verb with the clause it was going to take, setting us off balance as we try to sort out the thought. It’s all a bit rough and ready, as the two instances of was in close proximity only confirm.
But to help ourselves practically and to conclude justifiably that this sentence is awkward or wooden, we have to be able to point to the structural theory that governs modern English, a theory that will indeed change with time, but which we must assume to be a constant standard or else risk falling into the dizzying whirls of do whatever you want or you know what I meant. (And the fact that we can even speak of a theory changing with time is enough to show that what we mean by theory or principles or standards is not metaphysical, but practical—a long and winding distinction we best leave for now to the philosophers.)
So what do we need to know, then, to set this sentence aright? As is always the case, we begin an analysis by isolating subject from predicate: What I realized | [was] it was going to take a long time to heal. With this separation we can see that the main verb [was] is a copula, or linking verb, and that means that the sentence intends to assert an identity between the subject and predicate—a logical identity that should be expressed in a grammatical identity as well. What accounts for the awkwardness of the sentence is that the predicate comprises an independent clause (it was going to take) when it should assume the form of a noun of some sort in order to parallel the noun that makes up the subject, which we can see in the pronoun what. Simply change the independent clause in the predicate to a subordinate noun clause, and the path is made grammatically straight: What I realized was that it was going to take a long time to heal.
Grammatically straight, but rhetorically not yet polished to a burnish. The subject phrase what I realized foretells what the predicate states (something called an anticipatory construction), and this accounts for the somewhat lazy, sluggish tone. Exercising a little more revision, we can write I realized that it would take a long time to heal, making the noun clause in the predicate the object of the verb realized. And why would? Because in this context to realize something means to believe or suppose, and that is enough to warrant the subjunctive would, for no matter how strongly I might believe something, only the factual future will tell.
It is the theory of grammar that makes and explains the difference between independent and subordinate clauses, between nouns and noun clauses. All this terminology (and every art and science has its own set) gives us a way to recognize a problem, and supplies us as well with a way to revise knowingly—an insider’s knowledge that can answer why and so better our work.