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I came across some present perfect language exercises that I question.
Choose Present Perfect Simple or Continuous:
The place looks like a bombsite! What _____________ (do) all day?
Well, I've chosen "have you done" but the answer is "have you been doing". Why?
The British Museum has also announced a forthcoming exhibition of artifacts from the Stonehenge period which they _________________ (gather) over the last five years.
The answer is "have gathered", but I can't understand why. If you have "over the last five years" it seems to me this action was in progress during this five years.
Please, help me.
Thank you in advance!
Well, thanks for the comments, but to me, it isn't a duplicated question because I understand each tense separately and the idea of completion of the present perfect and the ongoing idea of Present perfect continuous. My question is: where is the completion idea in the second example? Let me explain myself, I thought in the second example the artifacts were being collected like in different events for five years. Some artifacts were collected, then after a given time more were collected over the period of 5 years they haven't collected all at once. And they won't stop collecting after the exhibition. I don't know if I'm making myself clear enough. But I've been looking for an explanation for this and I found one on Martin Hewings' advanced grammar in use book: "present perfect suggests that the activity happened only once or on a specified number of occasions".