Change the active into the passive
1/ My brother has just repainted the bicycle
The bicycle has just been repaired by my brother. 
2/ The artists are painting a big picture in front of the town hall
A big picture is being painted in front of the town hall by the artists. 
3/ They must widen the road soon
The road must be widened soon. 
4/ Nobody has ever treated me with such kindness
I haven't ever been treated with such kindness.