Creating a VLOOKUP with multiple lookup values

Hi,

I am creating a rota and can create a VLOOKUP successfully to see how many hours each shift contains, however I need this to actioned for a weeks worth of shifts e.g. Monday 12:00-18:00 is 6, Tuesday 10:00-16:00 is 6, Friday 18:00-22:00 is 4.
I have the rota showing the shift times and want the total box to show the total number of hours for this weeks worth of shifts.
Can anyone help? Lehmans terms preferable please as I have searched Google but can't make sense of some of their explanations :)

expand the problem description

Please add more specific information. Base on what you have I assume you want to sum weekly shift hours by employee and display all the employees on the summary sheet with their weekly shift totals. It this what you are trying to do? If this is so, then there is a better way than Vlookup. Please describe the problem further and I'll try to help. By the way what is a "rota?"