测定皮肤的酸碱度，最常用的是（）
A.蓝石蕊试纸；
B.淀粉-碘化钾试纸；
C.PH试纸；
D.刚果红试纸。
参考答案：C
With the help of the foreign experts, they produced ___ washing machines in 2003 as the year before. [ ]
A. as twice many
B. as twice as many
C. as many as twice
D. twice as many
构成假性胰腺囊肿壁的组织应为
A．内皮细胞
B．柱状细胞
C．纤维组织
D．周围的器官及纤维组织
E．粘膜细胞
