Present Perfect Continuous
has/have been + verb + ing
1) To emphasize duration (i.e. all day long, all night, for hours etc.)
2) Started in the past and is still going on
3) Started in the past and has just finished/you can see the result
4) Can signal irritation
1) We have been working for hours to get this finished
2) She has been crying all day since he broke up with her at breakfast.
3) You have been running really hard out there for you are all sweaty.
4) You have been going on about this for ages: let it go now.
Past Perfect Continuous
had been + verb + ing
1) To emphasize a longer action in the earlier past
1) Before you called, I had been working very hard on my final. project.