A Word, Please: The dummy word that holds things together

Have you ever thought about the word “do”? My advice is don’t.

The word “do” is one of the bugbears of English that make our language incredibly difficult to master — for nonnative speakers and even for people born into the English-speaking world. Almost no one fully understands “do.” The people who use it correctly do so through osmosis, not understanding.

To see what I mean, consider the formula for making questions in Latin-based languages like French. In other languages, to make a question, you often just take a statement and swap the places of the subject and verb. “Vous voulez fromage” (You want cheese) becomes a question when you switch the positions of the pronoun and the verb: “Voulez-vous fromage?” Simple.

There are exceptions, of course — situations trickier than this. But this is the basic formula. It’s called inversion, because you invert the position of the subject and verb.

Try that in English. “You want cheese.” “Want you cheese?” “He saw a great movie last weekend.” “Saw he a great movie last weekend?” As we’ll see in a minute, sometimes this process actually works in English.

But not in these examples. Examine all these questions and you can see that something is missing — a little-understood word known as a dummy operator. It’s the word “do,” and it’s how we form questions like “Do you want cheese?” and “Did he see a great movie last weekend?”

“Do” has two main jobs. First, it’s a regular old verb. “Do the dishes.” “I don’t do windows.” “I do.” In that job, it works the same as any other garden variety verb. But on top of that, it has a special job — that of dummy operator.

In grammar, an operator is an auxiliary verb that gets moved around to form questions and do a few other special jobs. It’s part of a broader group called auxiliary verbs that work as helpers with other verbs.

English has a number of auxiliaries; “have” and “be” are the regular ones. We see them in sentences like “I have walked” and “I am walking.” There are also modal auxiliaries like “can” and “must,” as in “I can have dessert” and “He must leave.”

These auxiliaries are operators, which means they can move around to do things like form questions: “Have I walked?” “Am I walking?” “Can I have dessert?” “Must he leave?”

Notice that when your sentence has an auxiliary verb, an inversion process like the one used in so many other languages works in English too. “I can leave.” “Can I leave?” The problem is that not all English sentences have auxiliary verbs. “I walk.” “Alex quit.” “Ruby knows.”

So to make these into questions, we call in a specialist — the dummy operator “do.” “Do I walk?” “Did Alex quit?” “Does Ruby know?”

Here’s how the Oxford English Grammar explains it: “Auxiliary ‘do’ is a dummy operator, since it functions as an operator in the absence of any other auxiliary when an operator is required to form questions, to make the sentence negative, or to form an abbreviated clause, as in ‘My sister likes them, and I do too.”

To me, the word “dummy” emphasizes how “do” doesn’t have any meaning — not in these sentences, anyway. Modal auxiliaries like “can” tell us something about possibility. Basic auxiliaries like “have” change a verb’s tense, telling us when something happened.

Auxiliary “do” doesn’t. Like a dummy in a store window, it has no substance of its own. It’s just there to help you arrange the things that actually matter.

JUNE CASAGRANDE is the author of “The Best Punctuation Book, Period.” She can be reached at