demanding Synonyms

petitioning squeamish stern strenuous stressful strict stringent summoning superincumbent tall taxing testing tiring soliciting severe possessory postulating punctilious punishing punitive requiring rigid rigorous rough scrupulous seeking selective toilful toilsome gruelling sandbagging persnickety bratty nerve-wracking unpermissive pernickety picky back-breaking choosy supercritical time-consuming grueling backbreaking tough troublesome trying ungrateful unsparing uphill upstream