Doubtless with the generous stipend you give her.Sin duda con el generoso salario que le has dado.
Doubtless it's the work of some harmless crank.Sin duda es obra de un maníaco inofensivo.
Further research will doubtless provide more detailed and reliable information ...Una mayor investigación sin duda ofrecerá información más detallada y confiable ...
Doubtless he has come to make ...Sin duda ha venido a mostrar ...
... is certainly difficult and doubtless painful.... es ciertamente difícil y, sin duda, doloroso.