在血平板上能形成草绿色溶血环的细菌是（）
A.铜绿假单胞菌
B.甲型溶血性链球菌
C.肺炎链球菌
D.γ-型溶血性链球菌
E.淋病奈瑟菌
参考答案：B, C
--- I ____ so busily recently that I ____ no time to help you with your maths.
---That’s OK. I can manage it by myself.
A．had been working; had had
B．have been working; had
C．have been working; have
D．am working; will have
