1. He sent the girl a letter.
→ A letter was sent to the girl by him.
→ The girl was sent a letter by him.
2. She is showing her friends the new computer.
→ Her friends are being showed the new computer .
→ The new computer is being showed to her friends by her.
3. Her mother often tells the girl tale stories.
→ The girl is often told tale stories by her mother.
→ The tale stories are often told to the girl by her mother.