对可疑生育遗传病患儿的孕妇做羊水穿刺检查的时间是()
A.妊娠4周
B.妊娠8周
C.妊娠12周
D.妊娠14周
E.妊娠16周
参考答案:E
Why didn't you tell me there was no meeting today? I all the way here through the heavy snow.
A.needn't have driven
B.can't have driven
C.mustn't have driven
D.shouldn't have driven
下列关于工业锅炉分类错误的是()。
A.锅壳式锅炉主要分立式和卧式两种
B.立式锅壳式锅炉有纵置式和横置式等
C.卧式锅壳式锅炉有单炉胆、双炉胆、回火管和水火管等
D.水管式锅炉主要分直水管和弯水管两种