煤层上覆的岩层称为(),煤层下伏岩层称为()。
参考答案:顶板;底板
The weather turned out to be fine yesterday. I __________ the trouble to carry my umbrella with me.
A.should have taken
B.could have taken
C.needn’t have taken
D.mustn’t have taken
个体对批评和教训有认识但无改正行为时,是自我中缺乏()的表现。
A、注意力
B、想象力
C、意志力
D、表现力