What are the rules of present perfect tense?

Related questions

1. Is called past tense?
2. Does present perfect tense?
3. What is past tense and types?
4. How do we use present perfect tense?
5. What is the structure of present perfect tense?
6. When present perfect tense is used?
7. What is perfect aspect in grammar?
8. What is perfect tense in English?
9. What are the forms and functions of present perfect tense?
10. What is the use of ago?

Tags

1. #simple
2. #perfect
3. #order
4. #thing
5. #present
6. #choose
7. #helping
8. #participle
9. #typical
10. #action
11. #sentence
12. #auxiliary
13. #subject
14. #person