1. It's understood that Bitexco Tower is the tallest skyscraper in Viet Nam

2. It is reported that the first temple existed during the reign of Le Thanh Tong in the 15th century

3. It's believed that Phong Nha Cave was found in the 16th century by Cham people

4. It's hoped that the site of the Perfume Pagoda was discovered over 2000 years ago

5. It's known that the government was conducting a project to investigate the harmful effects of the air pollution

Công thức Câu bị động It is said that

Trong câu chủ động: S1 + say + that + S2 + V2 + …

Trong câu bị động: It is said that + S2 + V2 + …

– Từ said trong cấu trúc It is said that có thể thay thế bằng các từ thought (nghĩ), believed (tin tưởng), supposed (cho là), reported (báo cáo, tường thuật), expected (mong đợi), known (biết), considered (xem xét).