Используйте «arduousness» в предложении

1. Continuing their rapid progress up the line, the groaning refrain was soon suffused with a more melodic chanting coming from those more used to heavy laboring activity, and the sounds were of the kind made in unison that helped to mitigate the arduousness and boredom of those efforts

2. were of the kind made in unison that helped to mitigate the arduousness and boredom of those