13,A sandcastle is being built on the beach

14,English was being learnt when I came 

16,TV wasn't being watched by Hoa when we came 

19,The school gate has just been painted 

20,A lot of money has been stolen by the thief in my house

23,His house hasn't been bought 

1.A sandcastle is built by him

2.English was learnt by him when I came

3.TV wasn't wathced by Hoa when we come

4.The school gate has just painted by him

5.A lot money in my house have stolen by a thief

6.His house hasn't bought