1. They speak English in Canada.
→ English is spoken in Canada.
2. They don't water the flowers today
→ The flowers weren't water today.
3. The students watched the "titanic" film on VTV2 yesterday.
→ The "Titanic" film on VTV2 was watched by the students.
4. Have your parents made this food?
→ Has this food been made by your parents?
5. The engineers can design this building easily
→ This building can be designed easily by the engineers.