$ sudo apt-get update
$ sudo apt-get install libgtk-sharp-beans-cil 

libgtk-sharp-beans-cil is installed in your system.

Make ensure the libgtk-sharp-beans-cil package were installed using the commands given below,

$ sudo dpkg-query -l | grep libgtk-sharp-beans-cil *

You will get with libgtk-sharp-beans-cil package name, version, architecture and description in a table

libgtk-sharp-beans-cil package basic information: