Present Perfect Continuous

The present perfect progressive expresses an action or actions that started in the past and continued until recently or that continue into the future.

The structure of the present perfect continuous tense is:

Subject + auxiliary verb + auxiliary verb + main verb

Have | has been +verb + -ing

The present perfect continuous is used with for o since with action verbs (learn, go, etc.) 

The present perfect continuous is used to when you finished an action that influenced the present

Examples: She has been writing for two hours.

                 I have been living here since 2001.

                 I have been working all afternoon.

                 He has not been speaking.

We can use it to refer to an action that has finished but you can still see evidence.

·         Oh, the kitchen is a mess. Who has been cooking?

It can refer to an action that has not finished.

·         I've been learning Spanish for 20 years and I still don't know very much.

It can refer to a series of actions.

·         He's been phoning me all week for an answer.

With non-action verbs (know, be, etc.) use the present perfect continuous with for or since

Example: I’ve known her for ages

Remember that the Present Perfect Continuous has the meaning of "lately" or "recently." A question such as "Have you been smoking?" can suggest that you smell the smoke on the person. Using this tense in a question suggests you can see, smell, hear or feel the results of the action. It is possible to insult someone by using this tense incorrectly.