we use the present perfect continuous to show that something started in the past and has continued up until now.
1. An action that started in the past and continued up until the present Example : The cat has been hiding under the couch for over an hour now. She has been sneezing since she got here. Sam has been working as a teacher since he graduated. He has a stomach ache because he has been eating too much. What have you been doing since I left?
2. An action that has just stopped or recently stopped Example : I'm tired [now] because I 've been running . Why is the grass wet [now] ? Has it been raining ? You don't understand [now] because you have n't been listening .
3. To show something was happening lately Example: Recently, I have been making more and more money with my business . She has been feeling much better lately . Have you been jogging lately ? They have been losing on all matches recently.
For and Since with Present Perfect Continuous Tense We often use for and since with the present perfect tense. Example: I have been studying for 3 hours. I have been watching TV since 7pm. Tara hasn't been feeling well for 2 weeks . For can be used with all tenses. Since is usually used with perfect tenses only.