消毒是指()
A．杀死细菌
B．杀死病毒
C．杀死芽胞
D．杀灭病原微生物
E．杀灭所有的微生物
参考答案：D
---I did very well in the Maths exam yesterday.
---I did _____ . I got full marks.
A．no better
B．no worse
C．even worse
D．not better
机械找正、地脚垫总厚度不应超过（）。
A.1mm
B.2mm
C.3mm
D.4mm
