【简答题】半导体材料按导电载流子类型分为( ) 和( ) 。
【判断题】从事特种作业(如电工、焊工、辐射、病原微生物等)的人员,必须接受相关的专业培训,通过考核并持有相应的资质证书才能上岗。
【判断题】从事特种作业(如电工、焊工、辐射、病原微生物等)的人员,必须接受相关的专业培训,通过考核并持有相应的资质证书才能上岗。()
【判断题】从事特种作业的人员如:电工、焊工等必须接受安全技术培训,通过考核并持有《特种作业人员操作证》才能上岗。取得《特种作业人员操作证》者,按要求年限进行复审。()
【简答题】成本项目是生产费用按经济用途分类的项目,一般分为( )、( )和制造费用三个成本项目。
【单选题】After she played the piano at school as people applauded.
A.
After she played the piano in school and saw that people applauded.
B.
After she played the piano and people applauded.
C.
After she played the piano in school, people applauded
【单选题】When Mary came, I _____ on the piano.