1. Active : He would be meeting them.
Passive : They would be being met by him.
2. Active : She would be watering this plant.
Passive : This plant would be being watered by her.
3. Active : He is meeting them now.
Passive : They are being met by him now.
4. Active : She will have watered this plant before I get here this afternoon.
Passive : This plant will have been watered by her before I get here this afternoon.
5. Active : She had watered this plant for 5 minutes when I got here
Passive : This plant had been watered by her for 5 minutes when I got here