What is the difference between these two sentences: He was writing a letter when someone knocked on the door and He wrote a letter when someone knocked on the door. Something’s just not quite right about the second sentence, but what exactly and why? Here’s where we can demonstrate the practical application of a little grammatical analysis and understand the difference between two very common verb forms.
The first thing to remember about revising is that you can’t be in a hurry. Our habit is to jump at some one word and hold it up to the light of our mind to find out what it is and what’s wrong with it. In the first sentence, for example, we might choose the word writing and ask whether that’s the correct form. But words work because they work together, and so it is important to look around a word we alight on in our analysis to determine its life with other words in the larger statement. That means that it’s better to single out a sentence in its entirety, then identify its clauses. From there, take one clause, find its verb, and then move to the phrases and words that fill out that clause. It’s not as elaborate as it sounds; it is, though, methodical.
So if we take the first sentence, we should see two clauses: the independent clause he was writing a letter, and the subordinate clause when someone knocked on the door. (This second clause is subordinate because it begins with the subordinating conjunction when.) The verb of the first clause is not one word, but a phrase, was writing. Let’s examine this closely. When more words than one are necessary to formulate a verb, the principal, or notional, verb—what it is we’re really talking about—always comes last in the verb phrase. So what this clause wants to say about the subject he has something to do with the act of writing. When a verb, in the form of a present participle (a verb form that ends –ing), is combined with some form of the verb to be (the verb was here), the construction that results is called the progressive aspect.
The term progressive refers to the fact that the action of the verb is seen to be ongoing, incomplete, continuing—all the notions that some other languages collect under a tense called the imperfect. English does not have an imperfect tense, and the progressive aspect is not (as some grammar books have it) a tense. Verb aspect refers to the manner—not time—in which the action of a verb is to be understood. If he, the subject, was writing, the grammar intends to create a mental picture in which we are to see something going on or continuing: there someone is at his desk, writing and writing when suddenly something very definite and defined occurred: someone knocked.
The verb knocked works alone. It is not part of a phrase, and that observation marks it as the simple past tense. Its aspect is called terminate, which means the action is to be seen as having both a beginning and an end; it’s complete: the knocking started and it stopped, unlike all that writing the subject he was doing in the first clause. The terminate aspect of a verb is the simple verb form (whatever its tense) used alone. We are to see, then, that the progressive aspect of the first clause is creating the space, so to speak, in which the piercing action of knocked occurred. The progressive was writing is the fabric, and the terminate knocked is the needle. And thus a context is woven.
Now if we examine the verb phrases of the second sentence, the verb of the second clause there, knocked, has remained the same, but the verb of the first independent clause has changed aspects. The verb wrote is now standing alone for the subject he, which means its aspect is no longer progressive, but terminate, just like the verb knocked in the subordinate clause. And what’s the result of that? The two actions are portrayed as complete, but are being connected at the same time with the word when, a conjunction that means just at the very moment. Now there’s nothing wrong with using the conjunction when, but things can go existentially awry when grammatical construction works against reality as we experience it. We don’t usually write a letter in a moment, and so to construct that verb in the terminate aspect suggests that it was, well, a pretty short letter. We can say that he dropped a plate when someone knocked at the door, because the act of dropping has a quick beginning and end. But writing is usually ongoing, taking up a stretch of time, and so that reality, and the thought that represents it, needs a grammatical structure that conforms to it.
Grammar serves thought, not the other way around. Our ideas, which come from the world as we know it, take shape in a sentence, so if what we’ve written doesn’t seem to say what we want to say, we can examine the form to find where the problem lies. Verb aspect, terminate and progressive, has a subtlety we might think at first unnecessary, but what’s going on around us, what we’re involved in from moment to moment, is a much more nuanced affair that we are usually inclined to believe. And sometimes that’s apparent when a sentence just doesn’t seem right.
You might also find this earlier post, Wrote or Has Written, helpful. And if you would like to subscribe to this blog to receive a new post free every Tuesday and Thursday morning, you may do so at the bottom of this page. Thank you for reading Writing Smartly.