隐孢子虫的生活周期5~11天,电镜下可在病变肠粘膜标本中观察到滋养体、裂殖子与裂殖体,雌、难配子体,子孢子与卵囊等不同发育阶段。()
Nowadays people who drive automobiles take various () against accidents.
A.precautions
B.preparations
C.prescriptions
D.prohibitions
We enjoyed ourselves very much at the party.You () with us.
A.must have come
B.should have come
C.would have come
D.might have come
液压电梯的特点是()。
A. 低噪声
B. 高耗能
C. 运行平稳
D. 安全性好