For a db person, LINQ can be frustrating. I need to convert the following SQL into Linq.

SELECT COUNT(o.objectiveid), COUNT(distinct r.ReviewId), l.Abbreviation
FROM Objective o
JOIN Review r
    on r.ReviewId = o.ReviewId
    and r.ReviewPeriodId = 3
    and r.IsDeleted = 0
JOIN Position p
    on p.PositionId = r.EmployeePositionId
    and p.DivisionId = 2
JOIN Location l
    on l.LocationId = p.LocationId      
GROUP BY l.Abbreviation     

The group by nested example might be the way I have to go, but not sure. Doing one group by I have used the following code:

var query = from rev in db.Reviews
                              .Where(r => r.IsDeleted == false && r.ReviewPeriodId == reviewPeriodId)
                from obj in db.Objectives
                              .Where(o => o.ReviewId == rev.ReviewId && o.IsDeleted == false)
                from pos in db.Positions
                              .Where(p => rev.EmployeePositionId == p.PositionId && p.IsDeleted == false && p.DivisionId == divisionId )
                from loc in db.Locations
                              .Where(l => pos.LocationId == l.LocationId)
                group loc by loc.Abbreviation into locgroup

                select new ReportResults
               {
                 KeyId = 0,
                 Description = locgroup.Key,
                 Count = locgroup.Count()
               };

    return query.ToList();

What is the correct way?

Thanks