В пассивный залог. 1) Documentaries about wildlife in the African savanna are being filmed by our team this week. 2) "Titanic" was broadcast yesterday by three channels at the same time.

Passive —> Active

1) Documentaries about wildlife in the African savanna are being filmed by our team this week. - This week our team is filming documentaries about wildlife in the African savanna.

2) "Titanic" was broadcast yesterday by three channels at the same time.  - Three channels broadcast  "Titanic" at the same time yesterday.