Say how long I have been doing something

In A2 you talked about how long something lasts with the perfect: I've lived here for five years (A2 #5). This tense has a partner — the continuous perfect, the Present Perfect Continuous. You need it when what matters is not what has been done, but what a person is busy with and how long the process has already been going on.

The form is built from two familiar parts: from the perfect — have or has and been (the third form of be), from the continuous tenses — the verb with -ing.

In a short answer been is not repeated: only have or has. And been here does not mean "was" or "visited", as in I've been to London: it is only a link that joins the perfect to the continuous form, and it has no meaning of its own.

When it is used.

A process started in the past and is still going on — usually with for, since, How long…?: I've been learning English for three years. Many languages say this in the present tense ("I learn English for three years"), but English takes the perfect, because it measures the stretch of time from the past up to today.

A process has just finished, and its traces can be seen: You're out of breath. Have you been running? We do not see the running itself, but we see that the person is out of breath. In the same way: The streets are wet — it's been raining.

An activity that has been repeated lately: I've been sleeping badly lately. She's been calling me every day this week.

Compare with the simple perfect. The continuous form talks about the activity, the simple one about the result.

From this comes a practical rule: the question How long…? is usually answered with the continuous form, and How many…? and How much…? with the simple one. A number of finished things closes the action, while the continuous form keeps it open: I've read three chapters, but not "three chapters in progress".

With the verbs live, work, study, teach both forms are fine: I've lived here for ten years = I've been living here for ten years. The continuous form sounds a little more temporary: people use it about something that may soon change.

A note of annoyance. The continuous perfect is often heard in complaints: Someone's been using my laptop! The speaker sees the traces of someone else's activity and does not like it. The simple perfect would only report the fact. In the negative the difference is the same: I haven't been sleeping well — sleep has not been going well lately; I haven't slept — there is no result at all, I have not slept.

State verbs are not used in the continuous form. They describe not an action but the way things are: know, like, love, want, believe, understand, own, be. With them — only the simple perfect: I've known her since school. We've had this car for ten years. have in the meaning "own" has no continuous form, but in the meaning "experience, spend time" it has: We've been having problems with the car.

Don't say this. ✗ I've been having this car for ten years → ✓ I've had this car for ten years.

Check yourself. How do you say that you started waiting twenty minutes ago and are still waiting? Which form do you need in I've ___ (read) fifty pages, and why? Can you say I've been knowing him for years?