list the ways in which twin boys had made life of canterville ghost unbearable.

The Otis twins enjoyed plaguing the Ghost and tried to invent new methods of troubling him. They would hit him on the head with pillows and then have a go at him again with their peas-shooters. On Friday the 17th, the Ghost made elaborate plans to frighten all the members of the Otis family, especially the twins. However, the twins got to the Ghost before he could! They constructed a false ghost a sweeping brush, cleaver, turnip etc. The apparition frightened the Ghost so much that he abandoned his plans to frighten the Otis family. When he discovered that he had been fooled, he came across the poem the twins had written for him:

YE OTIS GHOSTE.
Ye Onlie true and Originale Spook.
Beware of Ye Imitationes.
All others are Counterfeite.

This was the twins method of plaguing the Ghost further. After this incident the Ghost abandoned all plans of frightening the Otis family.