It is sometimes difficult to differentiate between the present perfect simple and the present perfect progressive.
Compare the following sentences:
1. I have written 6 letters this morning
2. I have been writing letters all morning.
In example 1 (present perfect simple), the implication is that the action is completed and the focus is on the AMOUNT or QUANTITY of something (in this case, the letters).
In example 2 (present perfect continuous/progressive), the action may or may not be completed depending on the context (maybe you just finished writing letters, or maybe you have more to write). Example 2 does not express an amount or quantity, it focuses more on the DURATION (all morning).
In summary, present perfect simple focuses on AMOUNT/QUANTITY, whereas present perfect continuous focuses on DURATION. Compare the following:
1. I have eaten the chocolates.
2. I have been eating chocolates.
Example 1 focuses on the AMOUNT of chocolates, indicating that the chocolates are finished. In example 2, it focuses on the DURATION of the action, which may or may not be completed (there may still be chocolates to eat).
So far, we have seen that present perfect simple focuses on AMOUNT and present perfect continuous on DURATION. However, look at the following sentences:
I have been a teacher for 7 years.
I have had a car for 6 years.
In both sentences, present perfect simple is used when expressing a duration. Why is this?
This is because the verbs ‘be’ and ‘have’ belong to a group of verbs known as state (or stative) verbs. That is, they express a state (a feeling, or something permanent). In other words, they do not describe a physical action (for example: eat, dance, drink, sing).
Other state (stative) verbs include: like, dislike, hate, love. While action (or dynamic) verbs have continuous forms, state verbs DO NOT HAVE CONTINUOUS FORMS, as they are not physical actions.
Learning Present Perfect and Present Perfect Progressive
The best way to learn these tenses is to use hobbies and careers. For example:
I started playing guitar in 1999 and I still play guitar now, so I have been playing guitar for 17 years. In these 17 years I have learnt 200 songs and played 150 shows.