People know that he has trained very hard. He.... / It...
He is known to have trained very hard. / It is known that he has trained very hard.
We assume that the kids are sleeping. The kids... / It...
The kids are assumed to be sleeping. / It is assumed that the kids are sleeping.
People think that pirates hid treasures in the Caribbean. Pirates.... / It...
Pirates are thought to have hid treasures in the Caribbean. / It is thought that Pirates hid treasures in the Caribbean.
We believe the government has spent too little on education. The government... / It...
The government is believed to have spent too little on education. It is believed that the government has spent too little on education.
They expect that he will recover soon. He... / It...
He is expected to recover soon. / It is expected that he will recover soon.
People consider that Russia is having dangerous interactions. Russia... / It...
Russia is considered to be having dangerous interactions. / It is considered that Russia is having dangerous interactions.
Experts think that air pollution will increase. Air pollution... / It...
Air pollution is thought to increase. / It is thought that air pollution will increase.
People believe Columbus discovered America. Columbus... / It...
Columbus is believed to have discovered America. / It is believed that Columbus discovered America.
People say her new film is excellent. Her new film... / It...
Her new film is said to be excellent. / It is said that her new film is excellent.
They say that Emma plays the violin very well. Emma... / It...
Emma is said to play the violin very well. / It is said that Emma plays the piano very well.