根据短文内容及首字母提示，填写所缺单词。 Many people in Beijing have returned to school only because they have become parents. Parents are searching for help to solve a problem: the education of their 'only c 1 '. One student complained about his father, who liked smoking, always left the s 2 of smoke in the room and he could not do his homework there. Another wrote that his father often played Majiang and the n 3 kept him awake most of the night. Many parents know l 4 about home education and keep making mistakes. 'Parents' schools are badly n 5 .'' an official (官员) said. 1.______ 2.______ 3.______ 4.______ 5.______