The present perfect uses the following formula:
subject + have/has + (not) + past participle + other.
Have(n’t)/has(n’t) + subject + past participle + other?
We have two uses for the present perfect:
1) Past events with a strong connection to the present
- You haven’t eaten very much.
- I have ridden a camel.
- I haven’t read his letter.
- Have you seen my calculator?
- Haven’t you been to Canada? I thought you went last year.
2) With words of unfinished times
- I’ve played tennis 3 times already this week* and it’s only Thursday!
- I’ve seen that film already.
- I’ve lived in Germany since 1986.
- Have you ever seen a ghost?
- Has the postman come yet?
*this week = Use present perfect when the week is unfinished. When the week is over, use the simple past.
I went to the mall three times this week. I don’t want to go again next week.