hard-won

ambitious arduous burdensome challenging crucial demanding laborious onerous painful problematic severe strenuous tough troublesome

backbreaker bothersome difficile easier said than done effortful exacting formidable galling gargantuan heavy herculean immense intricate irritating labored no picnic not easy operose problem prohibitive rigid stiff titanic toilsome trying unyielding uphill upstream wearisome

easy effortless facile helpful nice trivial

calm free friendly manageable plain simple sociable straightforward uncomplicated