Найдите в каждом ряду глагол во времени группы Perfect Tense и укажите.

1. a) are determining; b) determined; c) has been determined.
2. a) have furnished; b) is being furnished; c) furnish.
3. a) turn; b) were turning; c) has turned.
4. a) meeting; b) will have met; c) are being met.
5. a) had refused; b) refused; c) refuse.
6. a) obtain; b) have been obtained; c) is being obtained.
7. a) had been offered; b) offered; c) shall offer.
8. a) will be added; b) are added; c) has added.
9. a) was discovered; b) has been discovered; c) discovers.
10. a) are following; b) will follow; c) had been followed.