In an excellent advanced grammar book, Exploring Grammar in Context by Carter & Hughes & McCarthy, this exercise was given on the present perfect.

(page 7, exercise 4, item c)

Choose between the present perfect and past simple tneses for the verbs in brackets. If you think both are equally possible, write both forms.

c) I [buy] a personal stereo but I [sell] it to my teenage duaghter as it [look] silly on me at my age.
My answer:
bought, have sold, looked (all simple past except for sell in the present perfect)
The book answer:
bought, sold, looked (all simple past)

Ofcourse, I want to know why I got it wrong. The reason behind my choice of the present perfect is that it seems that selling the stereo is what needs to be emphasized and brought to the foreground (page 4 under observations says: The examples we have looked at so far point to a difference between (a) things that we want to bring to the foreground and say ' This is newor important or relevant or connected in some way in my mind to NOW ' and (b) things that we want to report/narrate or simply to say ' This is not important any more, or not relevant to now, or I have chosen to separate it in my mind from now.'

Will any native speaker choose my answer without being frown at?
Another question on page 8:
Complete these sentences in any way you like, taking care to choose appropriately between the present perfect and past simple tenses.

d) A: Do you still have your school books from when you were a kid?
B : No, my parents ...

My answer : have thrown them all out.
Book answer: threw them all out.

The question is Why not present perfect just like when you say :
I have lost my books ( you dont have them now). Whereas when you say
I lost my books ( you may have them now as I lost them but then I found them)
I have eaten ( I am full now)
I ate ( I might be hungry now and can eat again).

By the same token, if we say My parents have thrown them all out (means I dont have them now)
The simple past will work but the present perfect will emphasize the fact that I dont have them or that the effect of throwing is still present now in the fact that I dont have them.

What do native speakers think?
Hi Magic,

I agree with you that "have thrown" precludes your having recovered the books, but that should not be an issue, because of the way the question and answer are framed. You don't have the books! Must we wonder if you recovered them and then threw them out again? You may argue that simple past is the better answer because there's nothing to justify using the more complex version.

- A.
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Magic79Will Could any native speaker choose my answer without being frowned at on?
Yes. I see the present perfect as a possible alternative to the simple past for the verb sell. Nevertheless, once I start with a simple past, I think I tend to continue using the simple past through the rest of the sentence.
Regardless of the guidelines so often given in books in terms of "current relevance", in the case of throwing out the books, what you need is an explanation of why you don't have the books anymore (My parents threw them out.) -- not a commentary on what your parents may have done at some point in their lives (They have thrown out my books.)
Recall also that the present perfect cannot be used with a definite time. It's an 'indefinite tense'. Therefore you can talk about "what happened when you were a kid", but not about "what has happened when you were a kid".
On the other hand, I realize that we don't know exactly when your parents threw the books out, but the context suggests that it probably wasn't very recently. So it must have been close to or shortly after 'when you were a kid' if not exactly then.

Thanks CalifJim and Avangi.
Special thanks for correcting my question as well. And thank you for explaining why the book preferred to use the simple past rather than the present perfect in the two questions cited above.
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I agree with all the responses to your question. I think the answer, in this specific case, should be simple past, for the reasons others have stated.

But you introduced another related issue as an example, and that is:

I have eaten.
I just ate.

It's logical to presume everyone has eaten sometime in the general past. When someone asks you, "Have you eaten?" they are
referring to a specific time (i.e. lunchtime) that probably preceded the question by minutes not hours and, in fact, lunch time may not even be over yet.

I see no reason why this question shouldn't be restricted to "Did you eat?"

The only logical explanation I've found so far is that the word "yet" requires the present perfect. And in the case of "have you eaten?" the word "yet" is "implied" making this explanation even more tenuous in my opinion.

Additionally, does that mean this construction is incorrect: "Did you eat yet?"

A teacher from England answered this question definitively "yes" but I'm not so certain that's true in American English?

Any ideas anyone?
Americans frequently use the simple past with yet.
Did you eat yet? is as common as mud here.

Hello everyone,
Very helpful thread and I have a question on this subject for CalifJim.
When the present perfect is used to denote "current relevance", is it true that the sense of "immediacy" or " newness" is needed for the use of the present perfect in similar situations? In other words, we can't go too much in the past when we use it because that sense of   "current relevance" somehow vanishes  ? That said, am I right that the present perfect wouldn't be appropriate even if we changed "when you were a kid" with "from last school year", and we're saying that sentence on the very start of the new school year :

A: Do you still have your school books from the last school year?
B : No, my parents trew them all out.

Thank you for the answer and for helpful explanations in this thread
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