Some differences between P.P. and P.P.P.

PRESENT PERFECT PROGRESSIVE	PRESENT PERFECT
1) Recent activity: to emphasize the recency of a past activity.  We often use “lately” or “recently.” Example: She's been working hard recently. 2) Emphasis on the duration or length of an activity Example: Jack has been painting for 4 hours (and he’s still painting). 3) Recently finished activity with a present result Example: I've been working in the garden, that's why my hands are so dirty. 4) No difference in meaning. Often the present perfect progressive and the present perfect can have the same meaning. This is often the case with verbs of living, occupation, or vocation) Example: I've been living in Dallas for 3 years. OR     I've lived in Dallas for 3 years	1) Indefinite time in the past (experience). Emphasis is on the completed action at an indefinite time in the past. Example: Susan's written 3 books (in her life). 2) Emphasis on QUANTITY Example: I've read 300 pages of Tom Smith's latest book. 3) Duration from past to present (see #4 of present perfect progressive) Example: Peter has worked for that company for 5 years.

Here are some examples of the difference between the two forms when referring to duration of an activity as compared to quantity: 

1. He's been driving for 6 hours.  He's driven 320 miles.
2. The civil war in Syria has been going on for two years. Over 100,000 people have died.
3. We have been learning grammar since class began. We have covered 3 chapters in the book.