`1`. This road isn't used very often
`2`. This house couldn't be sold at this price
`3`. The letter will be delivered next week
`4`. The room is going to be painted next week
Dạng cấu trúc : Câu bị đọng
Công thức :
Thì HTĐ : S + am/is/are + P2
Thì TLĐ : S + will + be + P2
Thì TLG : S + am/is/are going to + be + P2