Let’s take a good look at how the continuous tenses work.
|Future Perfect||will + have + V3||will + have + been + -ing|
|Present Perfect||have + V3||have + been + -ing|
|Past Perfect||had + V3||had + been + -ing|
The differences between the simple and continuous are very dynamic. This means that changing between them can:
- Change the feeling of a sentence
- Change the “implication” of a sentence
- Change the meaning of a sentence
- Create sentences that are actually impossible (so kind of wrong)
We’ll look at these one by one, but first I want to take you somewhere…
Imagine yourself in a helicopter. You’re high above the ground and you can see for miles. Feels good, doesn’t it?
Below you is a forest. You’re pretty high off the ground, so you can see the whole forest from here.
You can see where the forest starts and where the forest ends. From your point of view, the forest is complete.
Now, let’s jump out of the helicopter…
And land deep in the middle of the forest.
It’s dark and thick. You have no idea where the forest begins and where it ends.
But that doesn’t matter because you’re really experiencing the forest.
To you, the forest isn’t just a part of the landscape. The forest is EVERYTHING around you.
How is this related to the perfect simple and continuous?
The perfect simple tenses are like being in the helicopter. When you use these tenses, you have a feeling of completeness. It doesn’t necessarily mean the action is finished, but somehow there’s a feeling of completeness there somewhere.
In the same way that you can see the whole forest at once, you can see the whole action at once.
When you’re in the forest, it’s more like the perfect continuous tenses. The action is ongoing and probably incomplete. Even if it’s not specified as incomplete, the feeling is there.
In the same way that you can’t see the end of the forest, you can’t see the end of the action.
As usual, the best way to get a better feel for this is by checking out the details. So let’s look at the differences between the perfect simple and continuous tenses:
When only the feeling changes
Let’s look at a couple of sentences:
I’ve learned a lot this week.
I’ve been learning a lot this week.
What’s the difference here?
The answer is: not much.
But there is a small difference:
They “feel” different. One feels more complete and the other more ongoing.
Let’s see how this looks with our forest and helicopter:
When we say, “I’ve learned a lot this week,” we see all the learning at once. It doesn’t have to continue.
It’s like saying, “Wow. I know more now. Maybe I’ll learn more this week. Maybe not. But already this is satisfying.”
When we’re in the forest, we really feel that we’re deep in the middle of the learning. There is a feeling that the learning is going to keep going.
So when we say, “I’ve been learning a lot this week,” it’s like saying, “Wow. I’m in the middle of learning stuff and I’m going to keep learning more!”
While you’re in the forest, nothing is certain to end. Even learning. And never-ending learning is a good thing, right?
When the implication changes
Sometimes when we use language, we want to suggest something without actually saying it. That’s part of the magic of language and how expert users can really manipulate it. That’s where we get poetry, literature and awful jokes (see this post for some of those).
Let’s look at this sentence:
I will have worked for 40 years in 2020.
This is a perfect simple sentence and not a continuous one. So that means we’re in the helicopter.
Because we’re in the helicopter, and we’re looking down at the action (working for 40 years), we can see where the action started and where it finished.
And that means that there’s a suggestion here:
“When 2020 comes, I’ll be retired. My working days will be finished!”
So what about the continuous?
I will have been working for 40 years in 2020.
Unfortunately, now it’s strongly implied that this unhappy worker won’t retire in 2020 — he’s right in the middle of the forest and can’t see the end of it:
Remember that this is just an implication. In both of these sentences, the speaker could be the happy retiree or the unhappy guy who doesn’t like his job.
But which tense you use can suggest which guy we’re talking about. And that’s both powerful and kind of fun to play with.
When the meaning completely changes (almost)
How about this one?
I’d just eaten some cake when you called.
I’d just been eating some cake when you called.
This time, instead of me telling you, take a look at the picture below. Which sentence do you think matches the picture?
Yep. You guessed it. The simple sentence definitely shows a completed action. (I’d just eaten some cake when you called.)
With the continuous, the implication is that the cake is not finished.
The suggestion is so strong here that the two sentences almost have different meanings.
But remember, nothing is ever certain with this kind of grammar. It changes all the time and different people use it in different ways, but the examples above certainly show the different ways the relationship between tenses can work.
When you just can’t… probably
So, when can’t you use the continuous tenses?
Well, let’s look at these sentences. Which one doesn’t make sense?
I’ll have been achieving a lot by this time next year.
I’ll have achieved a lot by this time next year.
With verbs like “achieve,” “finish” and “start,” there is no forest. Well, actually there is. But it’s tiny. So not really a forest. More a little bit of grass. Which isn’t a forest at all.
That’s because the forest is so small (because these actions are so short), that you would easily be able to see the end:
The continuous is all about being deep in the process of something. As a result, we can only use it for longer actions.
What’s more, the acts of achieving, starting and finishing are all complete actions.
What else can the forest and helicopter idea offer us? Well, this view of the tenses can also explain one more easily confused grammar problem:
When you also just can’t… because of numbers
There’s another situation when you just can’t use the continuous.
Remember that the continuous is like walking in the middle of a forest? So the main point about the continuous is that it isn’t complete — that there’s probably still more to do.
So what about when we talk about numbers?
I’ve written 10 emails today.
I’ve been writing 10 emails today.
One of these sentences is definitely wrong.
Which one? And why?
That’s a good question, right? That’s why I’m leaving this one for you to answer in the comments section below. I’m looking forward to hearing what you think about this.