Hi
What’s the difference? Not much, but 1) probably one specific time in the past and 2) at some indefinite time or times in the past.
1) I understand you talked to the manager.
2) I understand you’ve talked to the manager.
No.Past indefinite shows the shortest time and Present perfect show the longest time.
Yes, it's possible.Hi
I understand you talked to the manager.
Someone saw Alan talking to the manager at about 3pm and reported to Simon.
At time of speaking, Simon says “I understand you (Alan) talked to the manager."
I understand you’ve talked to the manager.
Simon has spoken to the manager about the office’s cleanliness
The office is now very clean. It has been cleaned. The time of cleaning is not specified but the effect of cleaning up is being felt.
At time of speaking, Simon says “I understand you’ve talked to the manager."
Is this possible?
I understand why you selected the verb forms you did for your sentences, and they were both appropriate. However, in each case, the other form is possible.I understand you talked to the manager.
Someone saw Alan talking to the manager at about 3pm and reported to Simon.
At the time of speaking, Simon says “I understand you (Alan) talked to the manager."
If you add 'at three o'clock' to your sentence, then only the past simple is correct. Without a past-time marker, either form is possible.
I understand you’ve talked to the manager.
Simon has spoken to the manager about the office’s cleanliness. The office is now very clean. It has been cleaned. The time of cleaning is not specified but the effect of cleaning up is being felt. At the time of speaking, Simon says “I understand you’ve talked to the manager."
See my previous comments.
Past indefinite shows the shortest time and Present perfect show the longest time.