Modern English has six tenses, and a tense is the form a verb takes in a clause to represent the time of its action. Tense, then, means time. But time is a tricky thing, because time means more than just earlier, now, and later. We might expect something to happen tomorrow, for example, but what we expect might not just begin and end, but begin, continue on for some time, and then come to a conclusion. Time, strange to say, can appear differently. So how does that happen in English grammar?
How, for example, are we to understand the tenses of the verbs in this sentence: We will be having lunch tomorrow at that new place that opened downtown last week. That one sentence is referring to two happenings: the first is expected to occur in the future, and the second has already taken place in the past. But notice that what is expected to happen in the future, we will be having lunch, depicts the event as ongoing; there will certainly be a time when the lunch begins and another when the lunch will end, but it is the stretch of time between those two clock-points that seems to be important to the writer. The future event of having lunch is not so much a sharp-edged rock as a flowing river—continuing pleasantly on and on, going and ending who knows where.
We get that picture when we read the clause we will be having lunch because the verb has taken on a certain grammatical construction. A clause, as we know, is a group of words with a subject and a verb, but the verb of a clause is often made up of more than one word. When that is the case, we speak more accurately of a verb phrase. Here, we is the subject and the verb phrase comprises the three words will be having. (The noun lunch merely constitutes the direct object of that verb phrase, but it’s often helpful in analysis to bring the direct object along to preserve the meaning.) But what is the difference between will be having and simply will have?
Grammatically, the difference is called a change in aspect. The term aspect refers to the way one sees the action of the verb, and English grammar recognized three such aspects: simple, progressive, and emphatic. Not all tenses can be put into all three aspects, but choosing the right aspect in the right circumstances (usually the progressive over the simple) makes for a more subtle and accurate—and therefore more interesting—depiction of events. The construction formula, as I like to call it, for the progressive aspect is some form of the verb be + the present participle. That formula calls for two elements, but that does not necessarily mean only two words.
In our example, the verb phrase will be having breaks down into will be, the future tense of the verb be, together with having, the present participle of the verb have. The last verb in a verb phrase is called the principal, or notional, verb, meaning that’s the verb that carries the essential meaning, or notion, that one wishes to convey. In the progressive aspect, the principal verb takes the form of a present participle, which appends the suffix –ing to the verb’s infinitive form. (Remember that gerunds in English also use that same –ing suffix, but in the progressive aspect this same form must be understood as the participle because it is modifying, or describing, the subject, which is what adjectives do. A participle is an adjective, while a gerund is a noun.)
And with those elements, we have constructed a form of the verb that leaves the future action open and ongoing over time, the better to match the open-endedness of a pleasant conversation between friends. We can appreciate how this progressive aspect feels when we compare it to the simple aspect of the other verb in the sentence, opened. That verb, whose subject is new place, is a simple past tense in the simple aspect, whose formula is merely the tense of the verb as standardly constructed. And why would we not want the progressive aspect in this second clause as well? Because there was an ascertainable point in time when the new place opened, a day and hour when something happened, the consequence of which will be to the open advantage of friends having lunch. To match the aspect of the two clauses would have stretched the logic into an unrecognizable image: we will be having lunch tomorrow at that new place that was opening downtown last week. What?
Aspect is one thing, and tense very much another. Meaning takes shape in form, and so the more confident we are with the many possibilities of grammatical form, the more precision, and therefore interest, we can bring to what we are writing and saying.
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