孕妇分娩时阵痛是自然现象，与孕妇产前的精神状况没有什么关系。（）
参考答案：错
“How was ______ they discovered the entrance to the underground palace？” “Totally by chance.”
A．it that
B．he that
C．it when
D．he which
风湿性心脏病心衰服用地高辛13天，出现恶心、呕吐，室早二联律，除停用洋地黄外，治疗应首选
A．慢心律
B．心得安
C．钾盐
D．心律平
E．胺碘酮
