SQL to LINQ Help

Question

I am really struggling transferring this SQL to linq below, can someone help me


SELECT        tblService.FilledByID, SUM(refServiceType.ServiceTypeAvgHours) AS TotalHrs
FROM            (tblService INNER JOIN
                         refServiceType ON tblService.ServiceType = refServiceType.ServiceTypeID)
WHERE        (tblService.ServiceStatus <> 5) AND (tblService.ServiceStatus <> 7) AND (tblService.ServiceDateStart BETWEEN NOW() AND NOW() - 30)
GROUP BY tblService.FilledByID