详细解释:a. 艰苦的, 费劲的, 勤劳的
词型变化：
名词:laboriousness副词:laboriously英语解释：
形容词 laborious:
characterized by toilsome effort to the point of exhaustion; especially physical effort同义词：arduous, backbreaking, grueling, gruelling, hard, heavy, operose, punishing, toilsome