------“Where was Li Ming last night ?”

------“I saw him ____ his homework in the classroom.”

A．was doing

B．did

C．doing

D．to do

合并双侧肾动脉狭窄的高血压患者降压不宜首选（）

A.钙通道阻滞剂

B.血管紧张素转换酶抑制剂

C.利尿剂

D.β受体阻滞剂

E.α受体阻滞剂