This is Mary's ruler. Please give ____. [ ]
A. to her
B. it her
C. her it
D. it to her
答案:D
下列疾病中,属于择期手术的是()。
A.消化道穿孔
B.甲状腺功能亢进
C.胃癌
D.血气胸
E.肠扭转
在使用移动排烟机排烟时,烟机须安装在()