Answer:
1. What have you learned since you came here? How many friends have you made? I hope you have already met a lot of interesting people.
2. My roommate and I had some free time, so we went to a show.
3. I have just had lunch, but I did not have lunch yesterday.
4. Who wrote the play „Hamlet“?
5. How many games the team have won so far this season?
6. I don't know Carol's husband. I have never met him.
7. It rained a lot last week, but it hasn't rained much so far this week.
8. How many letters have you written since the beginning of the month?
9. When we were on vacation, the weather was terrible.
10. In her whole lifetime, Mary has never seen snow.
11. I don't know where Ammy is. Have you seen her?
12. When I got home last night, I was very tired and I went straight to bed.
13. Your car looks very clean. Have you washed it?
14. George was not very well last week.
15. Mr. Clark worked in a bank for 15 years. Then he gave it up.
Step-by-step explanation:
We use Present Perfect to talk about:
- unfinished actions that started in the past and continue to the present.
e.g. I don't know Carol's husband. I have never met him.
- a finished action in someone’s life
e.g. In her whole lifetime, Mary has never seen snow.
- a finished action with a result with a present
e.g. Your car looks very clean. Have you washed it?
- with an unfinished action indicated by the adverb of time (this week/month/year, today, since…)
e.g. How many letters have you written since the beginning of the month?
We use Past Simple to talk about:
- finished actions
e.g. Mr. Clark worked in a bank for 15 years. Then he gave it up.
- a finished action with no results in the present
e.g. When we were on vacation, the weather was terrible.
- with finished actions indicated by the adverb of time (last month/week/year, yesterday…)
e.g. When I got home last night, I was very tired and I went straight to bed.