`1.` Meat and vegetables are bought by my mother every morning.

`->` Meat and vegetables : danh từ số nhiều `=>` Tobe chia là "are"

`2.` His house is painted by Mr.John every year.

`->` His house : danh từ số ít `=>` Tobe chia là "is"

`3.` Many trees are planted in our school every week. 

`->` Many trees : danh từ số nhiều `=>` Tobe chia là "are"

`4.` Cakes are sold by him every day.

`->` Cakes : danh từ số nhiều `=>` Tobe chia là "are"

`5.` English is studied by Nga twice a week.

`->` English : danh từ số ít `=>` Tobe chia là "is"

`->` Cấu trúc (theo thì Hiện tại đơn):

$\text{*Active:}$ S + V0(s/es) + O.

$\text{*Passive:}$ S + am/is/are + V3(ed/BQT) + (by O).
 

1)meat and vegetables are bought by my mother every morning

2)his house is planted by mr.jonh every year

3)many trees are planted in our school every week

4)english is studied by nga twice a week