# aptitude install kde
Reading package lists... Done
Building dependency tree... Done
Reading extended state information
Initializing package states... Done
Reading task descriptions... Done
E: Unable to correct problems, you have held broken packages.
E: Unable to correct dependencies, some packages cannot be installed
E: Unable to resolve some dependencies!
Some packages had unmet dependencies.  This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.

The following packages have unmet dependencies:
  kde: Depends: kde-core but it is not installable
       Depends: kde-amusements but it is not installable
       Depends: kdeaddons but it is not installable
       Depends: kdeadmin but it is not installable
       Depends: kdeartwork but it is not installable
       Depends: kdegraphics but it is not installable
       Depends: kdenetwork but it is not installable