Exercise 1. Put the verbs in brackets in the present perfect tense.
1. I (already / visit) __________ our form teacher in the hospital.
2. John (already / read) __________ the letter from Mary.
3. We (not begin) __________ to learn for the test yet.
4. Nancy (be) __________ to Vietnam several times.
5. They (not start) __________ the project yet.
6. The Greens (be) __________ to many countries in the world so far.
7. We (go) __________ to that village to do volunteer work several times.
8. Our teacher (already / explain) ___________ to us how to use the printer.
9. My pen isn't here any more. Someone (already / take) __________ it.
10. Mai (not finish) __________ her homework yet.
1. Have aleeady visited
2. Has already read
3. Haven't begun
4. Has been
5. Haven't started
6. Have been
7. Have gone
8. Has already explained
9. Has already taken
10. Hasn't finished
;))![Unit 15 : Computer](https://i.imgur.com/thvnYcH.jpg)