我国采用的围生期定义是()
A.妊娠满20周到产后1周
B.妊娠满20周到产后4周
C.妊娠满28周到产后1周
D.妊娠满28周到产后4周
E.胎儿成熟到产后1周
参考答案:C
The film “Inception” is rather difficult to understand. _____ the director tries to show in the film is unknown to the general watchers.
A.That
B.What
C.Whether
D.Where
下列生物按形态特征划分的一组是()
A.牛和草
B.鱼和河水
C.空气和阳光
D.猫头鹰和鼠