An issue with the Debian installer

[Zack]

Hi, guys, how's it going? I got one question:

I installed the system using the CD 1. Everything was fine (the 
installation process). But, when the system runs, it shows the command 
line mode only, not the graphical environment, I mean, not GNOME. What 
should I do to resolve this issue? As I said above, all the installation 
process was ok. Thanks.