题目

—Did you go swimming last Saturday? —_______ I had a cold and stayed at home. A . Yes, I did. B . No, I don't. C . No, I didn't. 答案：C人体口腔上皮细胞与洋葱表皮细胞相比，没有的结构是 [　　] A．细胞壁、液泡B．细胞膜、叶绿体 C．细胞质、液泡D．细胞核、液泡