根据单词的首字母及汉语提示补全单词。 (1)My sister is very c_________. She knows many things. (2)My art teacher is not strict. He is very k_______. (3)She often helps her mother do housework. She is very h_________. (4)He is good at study, because he is h_________(辛勤的) (5)Is he p________?(有礼貌的)