When do you use the present progressive and the simple present for continuous actions?

Question

I am having trouble differentiating between these two tenses when dealing with continuous actions.

What I have learnt is that the present progressive is used to emphasize that an action is currently taking place as we speak.

However I don't quite understand what this means, since both

Comemos and Estamos comiendo.

can mean we are eating, they are both indicating that an action is currently in progress right now, so what exactly is the present progressive emphasizing?

Secondly, I'd like to know if there is ever an instance where you use the present progressive and can't use the simple present tense because it seems as though you can always substitute the simple present for the present progressive.

Answer 1

For things which are in progress and can take a while (like eating), we use the progressive, mostly as in English. In general you cannot substitute the simple present in this context. You can get away with it in questions, but the answer will revert to the progressive if appropriate:

—Hola, ¿qué haces? ("Hi, what are you doing?")
—Estoy horneando un pastel. ("I'm baking a cake.")

The simple present, for verbs like comer, is most often used to talk about

1. the immediate future: Ahora comemos, luego vemos la televisión. = "Now we eat, then we watch the TV."
2. a habitual action: En casa comemos sólo comida sana. = "At home we only eat healthy food."

The progressive present in Spanish is often equivalent to the English present continuous, but do note that it's not (usually) equivalent to the use of present continuous to express future planning:

"What are you doing tomorrow?"
"I'm taking the cat to the vet."

That would be translated using the periphrastic future (with ir + gerund):

—¿Qué vas a hacer mañana?
—Voy a llevar el gato al veterinario.

Answer 2

The use of these tenses is very similar to that in English, I think (my native language is Spanish).

• "Comemos" means "We eat".

• "Estamos comiendo" means "We are eating".

The second form emphasizes that it is something that you are doing right now.

Answer 3

My spouse is German and has a tendency to get these two tenses reversed rather often when speaking English. This has given me reason to think a fair amount about these two tenses.

In English, the difference between the simple and the progressive is more of a dichotomy than in Spanish. In Spanish the lines are more blurred between these two tenses than in English.

Here's an example. I have a pet hamster. It is late evening as I write this and the little guy is running on his wheel compulsively right now. Note, I used the progressive. However, I could use the simple for the same observation, in Spanish. Here's a valid dialogue:

A: El hamster ¿ya se levantó?

B: Sí, ya corre, hasta más no poder.

In English, B would have to use the progressive: "Yes, he's running on his wheel, to beat the band." But in Spanish, it could be expressed either with the simple present (corre) or with the progressive (está corriendo).

Now, there are situations where you might want to use the progressive in order to make the continuity especially clear and explicit. For example:

C: ¿Por qué no llamas a la tía ahora para ver si quiere que vayamos por ella?

D: Estoy comiendo. La llamo pero un poco más tarde, o si prefieres, la llamas tú ahora.

You asked, "I'd like to know if there is ever an instance where you use the present progressive and can't use the simple present tense." The C-D dialogue is such an example.

Note, there is an even stronger way to convey continuousness -- with "estar en proceso":

E: ¿Por qué no envuelves el regalo para Bruno ahora?

F: Estoy en proceso ahora mismo, y casi termino.

Note what "en proceso" does to emphasize continuity:

G: Why don't you wrap Bruno's present now?

H: Yes, I'm doing that now, OR Yes, I'm in the middle of that now, and I'm almost done.