class file

Question

hi;

i am doing final year project to my university. but i have to submit interim report. so please help me. 

actually i am doing "Human resource information system"  

·        Managing of employee details, Leave details/  Employee dismissals/Resignation/   Employee training/  Employee loans/  Maintenance of salary details/  Salary deductions/   Overtime calculation/   Monthly salary process. this is main  objects.  my problem is how i write use case diagram and class diagram and also sequence diagram. visual studio 2010 c# is fully object oriented language actually how i write class files and inheritance and so on....please help me and give some brief description to develop my project.

       thanks 

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