高血压合并肾功能不全，降压药宜选（）
A.血管紧张素转换酶抑制剂
B.β受体阻滞剂
C.噻嗪类利尿剂
D.血管扩张剂
E.以上都不是
参考答案：A
— Did you go to the beaches?
— No, mum is ill _____ and I _____ stay at home to look after her. [ ]
A. on bed; must
B. on the bed; have to
C. in the bed; must
D. in bed; have to
为消除铸铁件的内应力所造成的精度变化，需在加工前作（）处理。
A.回火
B.正火
C.时效
D.淬火
