Getting Lazarus to work

For my job, I need to learn Delphi. Instead of getting a commerical version of Delphi, I first checked out the repositary to see if there is on available for my Linux machine. The answer is simply yes, and is called Lazarus using Free Pascal. I download and install it with Aptitude. After it installed, it complained that it misses the Free Pascal source files. It seems the Apitiude does not do its job thoroughly. To have Lazarus to work, you also need the package of fpc and fpc-source, i.e.

sudo aptitude install fpc fpc-source

After, everything works as it should be.