Hi~I'm an English learner.For your question:it depends. If you just wanna write a sentence,either one is OK.If you wanna write an essay,you have to balance all the grammar in your essay.If it happened in the past,you should use I wrote a letter:if it happens at present and maybe you wanna emphasize it,you can say I have written a letter.Hope my understanding can be helpful for you.
As there is no time period given, the first usage is the better one.When the time is not indicated, is it possible to say:
"I wrote a letter"
OR
"I have written a letter"
As there is no time period given, the first usage is the better one.
But the reason I was asking is that I've been told by a self-asured "p..ck" that we always use the Present Perfect Tense when there is no indication of time.
Not always. The term "no indication of time" can be very confusing. We do not use the presnt perfect to describe a specific, completed action, unless it has just occurred.
There is a good explanation of this tense at Advanced English lessons
verbpage/presentperfect.
/A learner/
I've written a letter is the correct form.
I wrote a letter would be correct if the narrator pointed to the past with the previous sentence.
Why would you say "I wrote a letter" is incorrect? You might have read in a grammar book?
Thank you for your reply, but I'd like to hear from the teaching stuff./A learner/
If I am interested in the current result of an action I use the present perfect tense. I have written a letter.
If I am interested in when in the past the action took its place I use the simple past. I wrote a letter half an hour ago.
Anyway its often hard to me to distinguish which tense should be used.