道路运输驾驶员在考核周期内累计计分达到20分的，接受继续教育合格后，本次诚信考核周期内可以考核为A级。（）
参考答案：错
命题有真命题、假命题，定理也有真定理假定理[ ]
He must have been working really hard these days. This morning, I even noticed ______ behind his ears.
A．grey hair
B．grey hairs
C．the grey hair
D．much grey hair
