根据物质形成氢键能力不同进行分离的方法是
A．液-液萃取法B．沉淀法C．硅胶色谱法D．聚酰胺色谱法E．离子交换色谱法
参考答案：D
附睾尾部不规则局限性结节，质地坚硬，触痛，结节与阴囊粘连者，为（）
A.子痰
B.子痈
C.肾岩
D.附睾良性肿瘤
E.附睾恶性肿瘤
My father told me last night ______ we're going to the Food Festival this weekend.
My brother and I felt very excited. [ ]
A. whether
B. where
C. what
D. that
