effortful,"['arduous ', 'backbreaking ', 'grueling ', 'gruelling ', 'hard ', 'heavy ', 'laborious ', 'operose ', 'punishing ', 'toilsome ', 'difficult ', 'dragging ', 'exhausting ', 'tiring ', 'wearing ', 'wearying ', 'heavy ', 'labored ', 'laboured ', 'laborintensive ', 'labourintensive ', 'leaden ', 'plodding ', 'Sisyphean ', 'arduous ', 'straining ', 'strenuous ', 'difficult ', 'hard ', 'effortless ']"