Let’s exercise our grammatical muscles for a few minutes with a deceptively simple sentence. How should we explain the word shopping in this brief sentence: They went shopping. The point of theoretical questions like this, just like the point of physical exercise, is to keep at the ready. One could almost say that the answer is less important than thinking through the problem, stretching our understanding of how language works, and in doing so, keeping ourselves fit to find the right form for our ideas in the future.
I often hear students say they don’t know what questions to ask in analyzing a sentence, and my reply is invariably to begin by identifying clauses. That means that the first question is always, how many clauses does the sentence comprise? A sentence may have one clause or (theoretically) one hundred, but each of those clauses is a grammatical solar system in its own right, with its own laws and center of gravity or cohesion—a way of holding itself together to carry its meaning. A sentence is a rhetorical, or stylistic, device; a clause is a grammatical and logical one.
So if we pose that first question to the sentence at hand, we find only one clause, one combination of subject and predicate, something we want to say something about, working together with something we’re saying about it: they + went shopping. Inside every predicate is a verb, what is called a finite verb, a verb that has number and tense and thereby puts the statement into action. Here that finite verb is went, but no sooner do we identity that word as a verb, than we sense some action in shopping as well, and wonder whether that word too is a finite verb. They went, but they shopping? Hardly, so our short and sweet sentence has only one clause with one finite verb.
But what then is shopping? Let’s notice first that this word is in the predicate, that part of a clause that contains a finite verb. It works here quite obviously to complete the meaning of the verb went (words other than the finite verb are, in fact, called complements), and so we can take one step more toward our answer by looking first at the grammatical form of the word shopping. Grammatical analysis always—always—proceeds in two strides: form, then syntax. Form means grammatical element, and syntax means how that identified element works with other words in its clause, or grammatical solar system.
Thankfully, we have only two choices in answering the question of the form of the word shopping: participle or gerund. Both of these elements invariably end with the suffix –ing, but they function quite differently, exclusively differently, in fact. A participle is an adjective, describing something else, as all adjectives do by nature. In the sentence we’re examining, the only word capable of being described adjectivally is the subject pronoun they, but does the sentence mean that they, shopping, went, as if to characterize the manner in which they went, or went on their way? That’s a bit of a stretch, because we had to distort the original sentence in order to get it to mean that. Contorting is good sometimes in analytical exercise, but distorting is not.
So we are left with the conclusion that shopping must be a gerund, which is a noun, not an adjective. But how would that work? Let’s remember first where the word stands in the clause: in the predicate, which means that it is likely completing the meaning of the verb went in some way. It can’t be working as the object of went, because that verb is not transitive, and so cannot govern an object. A noun, though, can also be the object of a preposition, forming with it a prepositional phrase, one use of which is to express purpose; and the idea of purpose is rightly put in a predicate because purpose attends our actions. But where is that preposition in our sentence?
It is not, and that is no problem, no inexplicable inconsistency in the exercise of English grammar. So common is it, in fact, for us to omit words in our sentences, that grammarians have coined a word for it—elision, the omission of words otherwise grammatically or logically necessary. Elision can be a deliberate choice of style, or it can be the result of historical accident, what has happened to a language just by virtue of so many people using it for so long a time. Language hardens and sets, and its speakers come to accept the way in which it has developed.
And so they went shopping means, more fully, they went for shopping, where shopping can now be seen as the object of the preposition for. We no longer use the preposition, but it had to have been there once, as it still is when we say, you can’t blame him for trying or money is for spending. Or, indeed, as we might well say: language is for analyzing—at least when we really want to understand what’s behind all our thinking.
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