下面在定语从句中如何省略关系代词
1.The boy who is on the biue bike is my son.
The boy ____ _____ ____ ____ is my son.
2.The man who is opening the bank is Mr.Green.
The man _____ _____ _____ is Mr.Green.
3.The car that is on the right belongs to Mike,
The car _____ ______ _____ belongs to Mike
4.The bus that we are on will take us downtown
The bus _____ _____ _____ will take us downtown