$ sudo apt-get update
$ sudo apt-get install libgtksourceview2-2.0-cil 

libgtksourceview2-2.0-cil is installed in your system.

Make ensure the libgtksourceview2-2.0-cil package were installed using the commands given below,

$ sudo dpkg-query -l | grep libgtksourceview2-2.0-cil *

You will get with libgtksourceview2-2.0-cil package name, version, architecture and description in a table

libgtksourceview2-2.0-cil package basic information: