Relate more than one column to lambda Expression

Question

I have the query below that relates only the Processoid. I need to know how to relate processes and processes lists by Processoid and Grupoid. I have consulted in several groups and did not get an answer. Thankful.

            return processos.Join(
                processosPendentes,
                p => p.ProcessoId,
                pp => pp.ProcessoId,
                (p, pp) => new Processos
                {
                    ProcessoId = p.ProcessoId,
                    GrupoId = p.GrupoId,
                    Descricao = p.Descricao,
                }

            ).ToList();