I haven`t been fighting since long : you want to put an emphasis on the action -the results are visible but the continuous form does not tell us whether the action is finished or not. Although the person speaking may not be performing the action [fight] at the time of speaking, he may be going to continue it after speaking. The activity is not complete.Originally Posted by endeavor6636
I haven`t fought for years - you put an emphasis on the result.
There is often very little difference between the present perfect simple and the present perfect continuous. In many cases, both are equally acceptable.
I've lived here for 10 years and she has been living here for 12 years.
They've been working here for a long time and Andy has worked here for even longer.
When we want to emphasize the action, we use the continuous form.
I've been working really hard lately.
She's been having a hard time.
When we want to emphasize the result of the action, we use the simple form.
I've phoned 32 people today.
She's written a 64 page report.
Look at these examples to see the contrast.
I've been driving for 5 hours and I've driven 500 miles.
She's been speaking on the phone for 20 minutes and she's not managed to convince him yet.
We've been talking about this for months and we still haven't found a solution.
If an action is finished and you can see the results, use the continuous form.
Your eyes are red. You've been crying.
You're out of breath. Have you been running?
I hope it helps,