To establish a connection between the present and the past.
For example: She’s started the assignment.
to discuss an unfinished time period.
Example: I’ve written a rough plan this morning.
No time reference: I’ve written a rough plan now.
To indicate something that happened before now, without specifying when.
Example: I’ve collected plenty of information.
Common time expressions: ever, never, before, up to now, still, so far.
Example: It’s the longest I’ve ever had to write.
To talk about a past situation connected to the present.
Example: I’ve read all the books on the reading list; I have the notes now.
Common time expressions: recently, just, already, yet (with negatives or questions).
Example: I’ve just got up. Have you written your assignment yet?
Comparing Present Perfect and Past Simple:
Past Simple:
Refers exclusively to the past, usually with a specific time or implied time.
Uses time expressions indicating a finished time.
Example: I made notes on the most important things.
Present Perfect:
Establishes a link between the past and the present.
Does not specify a particular time in the past.
Employs time expressions indicating an unfinished time.