病原体进入人体后,是否引起疾病,主要取决于
A.病原体的数量B.病原体的毒力C.病原体的致病能力和机体的免疫功能D.病原体的侵袭力E.机体的抵抗能力
参考答案:C
简述中性点不接地系统的适用范围。
Greatly ________, the students made up their minds to carry ________ the experiment.[ ]
A. inspiring; out
B. inspired; on
C. inspire; through
D. inspire; away