- We have washed the boots. They are clean.
- Ann has finished school already.
- Sally finished school last year.
- I saw the film three years ago.
- This is the most difficult exercise I have ever done.
- This is the best building I have ever seen.
- I did not sleep well last night.
- I have never stayed in this hotel.
Present Perfect употребляется для результата или опыта без указания законченного времени; Past Simple — с указателями времени last year, three years ago, last night. После ever используется причастие прошедшего времени.