《说文解字•序》载:“秦书有八体,一曰大篆,二曰小篆,……八曰隶书”。《汉书•艺文志》亦载:“是时始建隶书矣,起于官狱多事,苟趋省易,施之于徒隶也。”材料反映隶书 A.是秦代八大篆书字体之一 B.是在楷书基础上发展而来 C.是汉代狱官为书写方便而创 D.其创建与抄录公文狱事有关While _________ along the street, I _______ an old friend of mine yesterday morning. A. I walking, came up B. was walking, came out C. I was walking, came on D. walking, came across