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I have been in the library.

I think that sentence suggests "I am still in the library now.", am I right? If I'm not, then what exactly does it suggest?

I have been in Japan.

I think that sentence suggests "I am still in Japan now.", am I right? If I'm not, then what exactly does it suggest?

The reason why I'm asking this is because one of my dictionaries says that "I have been in the library." suggests "I have been staying in the library; I am still in the library now." Is that right? (However, the book also says that "I have been to the library." suggests that "I went to the library some time ago." ) Is it true that "I have been in the library. " is the present perfect of "I was in the library."?

Thank you for taking your time reading my question.
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No, the current status is not unambiguously defined in present perfect situations.
This commentary by Phil White in another forum may help:

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Phil White wrote:

The present perfect here appears to be problematic (to me):
  • I've wanted to tell John what I think of him for a long time.
It seems to me that it is entirely ambiguous whether I have spoken to John already, whether I am likely to speak to him or indeed whether I have now (recently) ceased to want to give him a piece of my mind. I can imagine this sentence being uttered under almost all circumstances except having already spoken to him in the non-recent past or having lost the desire to speak to him (in the non-recent past).

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Other may disagree, but I think he's right.

I have been in the library.
To me this tells me that you were in the library until (very) recently. You may still be or not there.
In order to eliminate the ambiguity, IMO you need to say:
I have been in the library and still am (there).
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ViceidolI have been in the library.

I think that sentence suggests "I am still in the library now.", am I right?
No. It means you were in the library at some time in the past, and you are not going to specify when because it's not important.
You can say it when you are still in the library, however. Then it means you started 'being in the library' earlier and are still there (obviously). Nevertheless, in this case, you would probably say, "I have been here since ...", and give a time.
CJ
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Comments  
Thank you! That's a very good explanation. I understand now.
 CalifJim's reply was promoted to an answer.
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Good explantion, thank you very much, Jim.
More from Phil White. The prepositions are very important:

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Correct and unambiguous sentences would be as follows:

I have been to the bookstore. (I am no longer there.)
I have been to the US. (I am no longer there.)
I have been in the bookstore for ten minutes. (I am still there.)
I have been in the US for ten months. (I am still there.)
I have lived in the US since 1990. (I still do.)
I have been living in the US since 1990. (I still do, but I regard it as temporary or there is a likelihood that I will soon move.)
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