Inthefuture,more______shouldbeplacedontheeducationoftheyoung.
A、crisis
B、implications
C、impressions
D、emphasis
设A为3阶矩阵，为A的属于特征值1的线性无关的特征向量，为A的属于-1的特征向量，则的可逆矩阵P为（）
A、
B、
C、
D、
A、充分必要条件
B、充分非必要条件
C、必要非充分条件
D、即非充分地非必要条件
TheopportunitytoexploreandplayandtheencouragementtodosoCan________theperformanceofmanychildren．
A、withhold
B、prevent
C、enhance
D、justify
_______themovieIwouldhavefinishedmypaperlastSunday.
A、Inspiteof
B、Butfor
C、Becauseof
D、Asfor