Tolong jelaskan tntang Present Perfect Continous Tense sama Past Perfect Continous Tense kira apa perbedaan,persamaan dan bgimana grammarnya?

Present Perfect Continuous
-> Kejadian lampau dan masih terjadi sampai saat ini

Rumus: Subject + Has/Have + Been + Vi(+ing) + Object
Ex:  -Tom has been studying for two hours.
        -I've been teaching for 5 years.

Past Perfect Continuous
-> Kejadian yang sudah terjadi pada waktu tertentu di masa lampau.

Rumus: Subject + Had + Been + Vi(+ing) + Object
Ex: - I had been eating the trash before my friend came.
       - She had been crying before the dad took her candy.

Persamaan:
-sama2 menyatakan suatu pekerjaan yang sedang dilakukan secara berkelanjutan

Perbedaan:
-present : dilakukan pd masa kini dan masih berkelanjutan
-past : dilakukan masa lalu dan berkelanjutan pd saat itu

Grammar:
- present perfect cont :
S + has/have been+ verb-ing + C

- past perfect cont :
S + had been + verb-ing + C