医疗机构从业人员分为几个类别()。
A.3个
B.4个
C.5个
D.6个
E.7个
参考答案:D
The three college students did what they could _____ the two children, although they was in danger.
A.rescue
B.rescued
C.to rescue
D.rescuing
多数细菌和真菌在生态系统中的作用是( )
A.生产者
B.消费者
C.分解者
D.三种都不是