1. At last he returned (Active) to the little town where his childhood had been spent (Passive).
2. The latest surgical instruments were used (Passive) during this unique operation.
3. The trouble is that this student does not work (Active) properly at his English.
4. Before the experiment the substances are mixed (Passive) in a large cup.
5. The commission will consider (Active) this offer carefully before accepting it.
6. In spite of the fact that the report was short, it covered (Active) the subject completely.
7. This instrument is preferred (Passive) to all others because of its great reliability.
8. The doctor said (Active) that an urgent operation was needed (Passive).
9. They will do (Active) everything in their power to help us.
10. I hope (Active) we shall never deal (Active) with this matter again.
11. The results of the last experiment were constantly referred (Passive) to by the professor.
12. This airplane crosses (Active) the Atlantic in about 10 hours.