Hi,
The present perfect can be confusing. What you have to bear in mind in choosing between the present perfect and past simple is that actions in the present perfect *have an effect on the present*.
E.g:
I've lost my keys
=I lost my keys, and I don't have them now
I lost my keys
in this example, it is possible that I found they keys *before now*
I've cleaned the car
=It is still clean now
I cleaned the car
= I cleaned the car, and it is possible that it is now dirty.
I've lived here for ten years
= I still live here
I lived here for ten years
= In the past, I lived here, and I probably don't now. (Needs more
information)
I've already eaten
= I ate a while ago, and I'm still not hungry, so I don't want any food now.
(this is different in the USA...)
In his acting career, Bradd Pitt has starred in some great movies
= his career continues to the present day
It is also used to announce news:
"Hey everyone! John's crashed his car"
"The USA has declared war on Iraq"
"Listen up guys! I've won the lottery!"
Is is always used with "ever" and "never" because ever and never refer to all the time in your life up to the present moment:
Have you read "Romeo and Juliet"?
I've never lived in Russia.
With the lives of dead people, we use the past simple because their lives have no connection to the present:
Einstein never realized his dream of the "Unified Field Theory".
Miles Davis had a great influence on contemporary jazz.
Your examples:
I've lost my wallet
= I lost my wallet and I don't have it now.
I've smashed the window
= You presenting news of the window being recently broken.
It is very likely that the window is still broken (i.e. no-one has replaced
it)
If you want, you can say "Hey! I lost my wallet a little while ago and
I still don't have it". But "I've lost my wallet" is more succinct.
Remember that we also have to use the present perfect for life experiences, since past experiences in our lives make us who we are today:
I my life I've sailed through the Amazon, I've climbed several volcanoes and I've learnt 16 different languages... etc.
Here, you're descriptions are not time specific. If you want to be specific about what actually happened, the past simple is used:
In my life, I've sailed through the Amazon, I've climbed several volcanoes.... When I was in the Amazon I went to Manaus and arranged a tour in the forest and we hunted crocodiles....etc...
I hope this clears a few things up for you!
Blue.
Lenka said:
My English teacher told me we can use present perfect to say for example:
I have lost my wallet.
I have smashed the window.
and so on...
Is it true? if it is, I can´t understand when we can use this tense. The time when I lost the wallet ended, didn´t it?