The present perfect progressive tense forms talk about
1. actions that started in the past time and that is going on in the present time almost without
He’s been writing letters all day/since morning.
We’ve been living here almost a year/since last Christmas.
I’ve been waiting here for an hour already/since six o’clock.
2. actions that occur more or less frequently:
We’ve been meeting every Friday for years now/since we became friends.
I’ve been giving guest lectures regularly since April/ for six months now.
We meet every Friday
I give lectures regularly.
3. actions expressing intentions that are yet to become facts:
Don’t pay any attention to their promises; they’ve been promising to repair the
I’m so sorry; I’ve been meaning to see you for ages but I’m quite busy at work.
The Committee has been threatening to resign—but I don’t expect they will in
He’s been asking Sumathi to marry him ever since they first met.(without success)
We’ve been trying for a World Bank loan for a year now.(we haven’t got it yet)
They promised to repair the roof. (but they haven’t kept it.)
They’ve promised to repair the roof. (So I hope they’ll start the work soon.)
The Committee threatened to resign. (but they haven’t so far.)
The Committee has threatened to resign. (It’
He asked Sumathi to marry him. (This sentence merely narrates a definite act in the past.)
He’s asked Sumathi to marry him. (I she will./ He hopes she will.)
We tried for a World Bank loan. (but we didn’t / haven’t got it.)
We have tried for World Bank loan. (hopefully we will get it.)