
Originally Posted by
shun
Jwschang,
I guess you may have confused a few things. But I sincerely hope I am wrong.
You wrote:
> I define the Present Perfect tense as expressing
> an action that is already COMPLETED at the
> present time, OR an action BEGUN earlier
> and spanning a period to the present time.
>
My reply: Please recongnize that "an action that is already COMPLETED at the present time" is a past action, for example:
Ex: I met John on the street.
== The meeting is already COMPLETED at the present time.
(See my reply per (4) below.)
Also please be reminded that "an action BEGUN earlier and spanning a period to the present time" is a present action:(It is a present action but not ONLY that; it tells how long since.)
Ex: I live in Hong Kong. (Do you say:"I live in HK for two years"? In Chinese or some other language, yes; in English or some other language, no.)
== The living "BEGUN earlier and spanning a period to the present time", as I could not live here suddenly, and it must have begun earlier.
That is to say, you haved described Present Perfect as itself indicating either Simple Past or Simple Present. Through your merciful (Why "merciful"? I guess it could take away some of the confusion or pain of the Perfect tenses? It's an apt word to use here, though.) description, IMHO it seems that the three tenses are interchangeable, without a guideline to tell them apart.
You wrote:
> "Last week" is a point of time in the past,
> so no problem here. "For the past week"
> is a span of time that goes on still, so is
> considered incompatible with the idea of
> "completed" action.
>
My reply: Though in your message I see no restriction about tenses whatsoever, please be reminded of one common rule: Present Perfect doesn't stay with past time expression:(I have not heard of this rule, at least not in the way that you have put it as "past time expression". Correct rule would be: Past Perfect goes with Simple Past: I had eaten when he arrived.)
Ex: *I have visited there last week.
Therefore, perhaps for this reason, you didn't give illustrating examples for "for the past week":
Ex: I have visited there for the past week. (You have given an excellent example of what I didn't see necessary to give. It fits exactly my definition of the Present Perfect.)
== No matter how you describe "for the past week", it is still a past time expression and is supposed not to stay with Present Perfect. ("For the past week" refers to a period begun in the past, not JUST a simplified "past time expression".) Grammar writers cannot handle this, and this is the exact reason why they have to hide the Past Family away. (Why do you say "hide"? We still use them, and we don't have to follow what CERTAIN books or grammarians say. That is why even grammarians do not agree on everything among themselves.) What then is your opinion?