Page 477 - Practical English Usage 3ed - Michael Swan, Oxford

present perfect (4): progressive (or 'continuous') 458
The French revolution has influenced every popular radical movement in Europe since 1800. (ZOO-year-old event - present perfect)
Ann phoned five minutes ago. (very recent event - simple past) 11 both possible
The difference between the present perfect and the simple past is not always very clear-cut. It often depends on our 'focus': are we thinking mostly about the present relevance of a past event, or about the past details? In some cases both present perfect and past are possible with little difference of meaning.
We (have) heard that you have rooms to let. Has Mark phoned? OR Did Mark pJwne? I've given / [ gave your old radio to Philip.
458 present perfect (4): progressive (or 'continuous')
1 forms
havelhas been + -ing
[ have been thinking about you.
Have you been waiting long?
[haven't been studying very well recently.
For double letters in words like sitting, stopping, see 562. 2 continuing actions and situations
We use the present perfect progressive to look back over actions and situations which started in the past and are still going on.
I've been working very hard recently.
[t's been raining all day. I'm tired of it.
House prices have been going up steadily all this year.
We often use the present perfect progressive to talk about people's use of their time up to the present.
Hi! What have you been doing With yourself?""I've been trying to write a noveL
That kid has been watching 1V non-stop since breakfast. present perfect progressive: actions and situations which
started in the past and are still going on
House prices have been going up steadily this year.
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