多个用户使用单一表单登录

hello i need your help pleas guys i am new to work on vb.net 2008 and sqlserver 2005 i have a problem ... I make table 1(For employee),(For Employee fields are [empl_No,empl_ID,empl_Password,User_type]) ,,, In which User_type(Administrator and Instructor,Student) I want to know that When Admin login then show Form1 and when Instructor login the show Form2 and if student then form3... Now Plz correct my code ... hello i need your help pleas guys i am new to w