Необходимо написать в пассивном залоге1.Someone built the house twenty years ago2.Someone

1.The house was built twenty years ago.
2.The house was painted last month.
3. My wallet was stolen yesterday.
4.The grapes were left to dry in tge sun.
5.Most of the prisoners are visited once a month.
6. These cars are мейд in Japan.
7. The children were taught to be polite.
8.Ann's bike was found in tge river.
9.This wine was bought in France.
10. This vase was broken yesterday.
Можно еще в конце предложение написать by someone(кем-то)либо by them(то есть что-то сделано ими).By someone или by them глядишь по контексту.

Вообщем,passive voice необходимо понять сходу,чтобы позже не было провалов.

Пассивный залог (passive voice)указывает, что лицо либо предмет, выраженное подлежащим, испытывает деяние на для себя: the house was built (дом построен), (the vase was built - раза разбита)

Для того, чтоб получить форму глагола в пассивном закладе, нужен вспомогательный глагол to be в подходящем медли, личике и числе и причастие прошедшего времени (Participle II) означаемого глагола:

This building WILL BE DEMONSTRATED next month.
Это здание будет снесено в последующем месяце.

My dog HAS BEEN STOLEN.
Мою собаку украли

The house was built 20 years ago.

The house was painted last month.

My wallet was stolen yesterday.

The grapes are leaved to dry in the sun.

The prisoners are visited once a month.

These cars are мейд in Japan.

The children are taught to be polite.

Ann's bike was found in the river.

This wine was bought in France.

This vase was broken yesterday.