If Market Value (M.V.) > Face Value (F.V.) then the share is at premium. Therefore, share having market value (M.V.) = 120 is at premium.
If Face Value (F.V.) > Market Value (M.V.) then the share is at discount. Therefore, share having market value (M.V.) = 80 is at discount.
If Market Value (MV) = Face Value (FV) then the share is at par. Therefore, share having market value (M.V.) = 100 is at par.