1. Letters are typed in the office by Mary.
→ câu bị động thì HTĐ: S + is/am/are + V3/ed + (by+O) + time
2. You will be helped by his father tomorrow.
→ câu bị động thì TLĐ: S + will/shall + be + V3/ed + (by+O) + time
4. This bottle was broken by Peter.
→ câu bị động thì QKĐ: S + was/were + V3/ed + (by+O) + time
5. English is being learnt in the room.
→ câu bị động thì HTTD: S + is/am/are + being + V3/ed + (by+O) + time
6. My mind can't be changed.
→ câu bị động dạng động từ khiếm khuyết: S + can/should/have(has) to/ may ... + be + V3/ed + (by+O) + time
7. I hadn't been told about it.
→ câu bị động thì QKHT: S + had + been + V3/ed + (by+O) + time
8. Her telephone number isn't known by me.
9. The children will be brought home by my students.
10. The engine of the car has to be repaired.
11. A story is going to be told by teacher.
→ câu bị động thì TLTD: S + is/am/are + going to + be + V3/ed + (by+O) + time
13. Tea can't be made with cold water.
14. Some of my books have been taken away.
→ câu bị động thì HTHT: S + have/has + been + V3/ed + (by+O) + time
15. The meeting will be held before May Day.