MVC LINQ加入三个表

Question

我有3张桌子：

*USERS*
ID | USERNAME | ...

*SERVICE_NAME*
ID | SERVICE_NAME

*USER_SERVICES*
ID | ID_USER | ID_SERVICE

从表*USER_SERVICES*，我可以检查用户是否启用了服务。 到目前为止，这是我的LINQ，但它只返回实际至少一个服务的用户。

        var resultsServices = from p in USER_SERVICES
                      group p.ID_SERVICE by p.ID_USER into g
                      select new { ID_USER = g.Key, Services = g.ToList() };


        users = (from user in USERS
            join service in resultsServices on user.ID equals service.ID_USER
            where user.ID == service.ID_USER
            select new
            {
                user,
                service.Services
            });

我如何返回所有用户，即使他们没有启用任何“返回null”的服务？