1. Lý thuyết: Chuyển câu chủ động sang bị động với People/They + say/believe/think/claim/report… that…
Khi câu có dạng:

People/They + động từ tường thuật (say, believe, think, report, claim, rumor…) + that + S + V

Ta có 2 cách chuyển sang bị động:

Cách 1
It + be + PII + that + S + V

Ví dụ:
People say that he is rich.
→ It is said that he is rich.

Cách 2
S + be + PII + to + V

Nếu mệnh đề sau hiện tại / tương lai → to V
Nếu mệnh đề sau quá khứ → to have + V3
Ví dụ:
People say that he stole the money.
→ He is said to have stolen the money.

2. Câu trả lời chi tiết
1. They believe that Jim is going to study abroad.
Câu bị động

→ It is believed that Jim is going to study abroad.
→ Jim is believed to be going to study abroad.

Dịch nghĩa:
Mọi người tin rằng Jim sẽ đi du học.

2. People rumored that there was a ghost in that house.
→ It was rumored that there was a ghost in that house.
→ There was rumored to be a ghost in that house.

Dịch nghĩa:
Người ta đồn rằng có ma trong ngôi nhà đó.

3. Someone said that Jane would be able to win the contest.
→ It was said that Jane would be able to win the contest.
→ Jane was said to be able to win the contest.

Dịch nghĩa:
Người ta nói rằng Jane sẽ có thể thắng cuộc thi.

4. They claimed that everything they said was true.
→ It was claimed that everything they said was true.
→ Everything they said was claimed to be true.

Dịch nghĩa:
Người ta khẳng định rằng mọi điều họ nói đều là sự thật.

5. They reported that there was a serious accident on the main road.
→ It was reported that there was a serious accident on the main road.

Dịch nghĩa:
Người ta báo cáo rằng có một tai nạn nghiêm trọng trên con đường chính.

6. They don’t think that this camera costs that much.
→ It isn’t thought that this camera costs that much.
→ This camera isn’t thought to cost that much.

Dịch nghĩa:
Người ta không nghĩ rằng chiếc máy ảnh này đắt đến vậy.

7. Did they claim that they had managed to solve the problem?
→ Was it claimed that they had managed to solve the problem?
→ Were they claimed to have managed to solve the problem?

Dịch nghĩa:
Người ta có khẳng định rằng họ đã giải quyết được vấn đề không?

8. People didn’t expect that the building collapsed after the storm.
→ It wasn’t expected that the building collapsed after the storm.
→ The building wasn’t expected to collapse after the storm.

Dịch nghĩa:
Người ta không ngờ rằng tòa nhà lại sập sau cơn bão.