Shuihudi Qin bamboo slips(睡虎地秦简)FengZhenShi(《封诊式》),which includes two words"zizhou(自昼)"and"zixiao(自宵)".Currently,there is no good interpretation opinion in the academic community.According to the examples of"jizhao(既朝)"and"jixi(既夕)"in the ShiSangLi(《士丧礼》)and JiXi(《既夕》)sections of the book Yili(《仪礼》),"Zizhou(自昼)"and"zixiao(自宵)"should be read as"jizhou(既昼)"and"jixiao(既宵)"respectively,and trained as"when the morning sky just breaks"and"when the sun sets at night".The similarity between self phonetic characters and self phonetic characters should be feasible,as it conforms to the principles of phonology and is supported by examples and vocabulary in literature."Jizhou(既昼)"and"jixiao(既宵)"are time nouns used as adverbs in the simplified text,and their syntactic structure is not affected after deletion.