英语中的复合句由主动语态变被动语态时，通常只需将主句谓语变为被动语态即可。如：
People say that he left a good name behind him. 人们说他身后留下了好名声。
→That he left a good name behind him is said by people.
→It is said that he left a good name behind him.
Everyone knows that the sun rises in the east. 人人都知道太阳从东方升起。
→That the sun rises in the east is known by everyone.
→It is known by everyone that the sun rises in the east.
但在某些特定语境中需将复合句中的主句和从句同时变为被动语态。如：
Jim told us that the teacher praised him today.
→We were told that Jim was praised by the teacher today. 有人告诉我们说今天吉姆受到了老师的表扬。