1. He seems to have finished the task.
2. Tom was said to be the strongest guy in the town.
3. All the guests are supposed to be wearing black suits.
4. She was heard to be singing in the ballroom at the ceremony.
5. He is known to be single.
6. She is supposed to come on time.
7. The train was seen to approach . ( <-- здесь я не очень уверен в ответе)
8. This little girl is expected to become a beautiful woman.
9. Her hobby proved to be interesting.
10. They are not likely to pass their exams tomorrow.
11. J. Dawson is believed to be the best player of the team.
12. That building is said to have been sold already.
1 a to have finished
2 c to be
3 a are supposed
4 b to be singing
5 a to be single
6 b to come
7 a to have approached
8 b is expected
9 to be interesting
10 c to pass
11 b is believed
12 a is said to