第30题: [单项选择]亚急性联合变性的病因()。 A. 维生素B12缺乏 B. 维生素B1缺乏 C. 维生素B6缺乏 D. 内因子缺乏 E. 叶酸缺乏 参考答案:A
第31题: [单项选择]{{B}}Passage One
Questions 26 to 28 are based on the passage you just heard.{{/B}} A. She will ask for another gift B. She will exchange it for something useful C. She will return it to the giver D. She will just keep it 参考答案:B 答案解析:[听力原文]26-28
In the United States, couples usually receive gifts from their relatives and friends