海绵动物的无性生殖方式有（）和（）两种。
参考答案：出芽生殖；形成芽球
— You've agreed to go.So aren't you getting ready?
— But I ______ that you would have me start at once. [ ]
A. didn't realize
B. don't realize
C. haven't realized
D. hadn't realized
PICC的尖端应该置于（）。
A.上腔静脉的下1/3段
B.右心房
C.上腔静脉的下1/3段到上腔静脉与右心房的连接处
D.下腔静脉入口处
E.上腔静脉入口处
