Present perfect tense

1. has been
2. have seen
3. has never seen
4. have known
5. have had
6. has given
7. haven't had, have had
8. have made
9. has examined
10. has prepared

1. Bill has been here since the 22nd
2. Last january i have seen snow for the first time.
3. In here whole lifetime, Anna has never seen snow.
4. I have known Greg Adams for ten years.
5. So far this week, i have two test and a quiz.
6. Up to now, professor williams has given our class five tests.
7. Since classes began i haven't much free time, i have several big test to study for.
8. Since the beginning of the twentieth century,medical scientists has made many important discoveries.
9. The Doctor has examine for a half hour.
10. The pharmacist have prepared the medicine since 09.00 o'clock.