A:
B:
C:2008
D:2012
禽流感病毒能使人、禽致病,同时也能利用它来防治禽流感,这种病毒细胞微小,结构简单。
肺动脉里流动的是动脉血.(判断对错)
--- What happened?
--- I am under the weather. I think I should go to see a doctor.