(Somebody has been rifling through my desk.)
I don't quite understand the meaning of 'has been rifling' here, I've met several similar sentences and i'm confused.
Does it mean sombody always rifles through my desk and this time he does so again, is there another way of saying this ? I need clear explanation.
Thanks a lot.
The form is used like the present perfect tense (Somebody has rifled through my desk), but it imples that the action took place over a period of time - it's progressive.
So, you can say "Somebody has shot my brother" (present perfect) - because it only happened once, but:
"Somebody has been shooting ducks" (present perfect continuous) - I've heard the sound of shooting many times, all day.
Simple past tense forms of these two sentences would be:
Somebody shot my brother. (Simple past).
Somebody was shooting ducks (Simple past continuous).
Simple past: Somebody rifled through my desk.
Simple past continuous: Somebody was rifling through my desk.
Present perfect: Somebody has rifled through my desk.
Present perfect continuous: Somebody has been rifling through my desk.
These are all true statements, given the original sentence.
Yes, it can be used this way. In this case, it's hard to tell. If your sentence was followed by "I wish I could find out who is doing this", then yes. But it still could have happened only once, but over a period of time - in which case the following sentence would be "I wish I could find out who did this".Does it mean sombody always rifles through my desk and this time he does so again, is there another way of saying this ? I need clear explanation.
To express an ongoing concept, you could use the present continuous with an adverb "always": Somebody is always rifling through my desk (and they have done it again)
The present perfect continuous was used because i) it is an action that happened in the past, but the focus is on the completed action in the present and 2) it was a continuous action. It happened over a period of time in the past, but has now stopped (at least for now).