To be successful in this job, it takes a substantial time commitment - when most people think of the life of a Senator, this usually comes to mind. (binghamtonhomepage.com)
27 October 2014 The advantages of serving on a study section, Alice says, more than justify the substantial time commitment. (sciencemag.org)
Because my classes average around 30 students, this activity was a substantial time commitment. (edutopia.org)