焦虑是( )。
A.情绪明显增高B.指情感处于抑制状态,表现为情绪低落C.表现为为了一点事就伤心流泪或兴奋激动D.无明确对象的内心紧张、害怕、担心、不安的体验
参考答案:D
国际学术界建议孕妇应从什么时期开始服用叶酸?()
A.孕前1个月
B.怀孕时
C.怀孕3个月
D.怀孕6个月
Junk messaging has been a headache for years, __the action taken by the authori-ties has not yet produced the results expected
A.as
B.but
C.so
D.before