病程中梅毒传染性最强的是（）
A.潜伏期
B.第Ⅰ期
C.第Ⅱ期
D.第Ⅲ期
E.恢复期
参考答案：B
This is a ___________. [ ]
A. desk
B. chair
Climbing Mount Tai great skills and not without risk.
A．requires; is
B．required; was
C．required; are
D．required; were
[ ]