PERFECT PRESENT - seeing examples


WE USE PRESENT PERFECT...

SOMETIMES because it is related to now,

sometimes because THERE IS NO EXACTNESS...

So, it depends on the case!

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take a look at these examples below:

http://1.bp.blogspot.com/-g8JlARi5jOk/TxxtTDmXZdI/AAAAAAAAARg/jy_EujmIHZ0/s400/050606_2.jpg
Let's imagine this answer: "Yes, I have..."

Well, she is not seeing it now, is she? Not anymore...
She saw it in the past, and, because IT DOESN'T MATTER EXACTLY WHEN,
she uses the Present Perfect instead of the Past Simple...



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another example
http://dynamic.pixton.com/comic/q/h/q/y/qhqyf6wm1fh6wo38_v3_.png
"It doesn't matter exactly when it happened"

That's why he doesn't use the simple past...
THERE IS NO PRECISION, NO ACCURACY...