赫尔巴特四段教学法的最后一步是()
A.系统
B.联合
C.方法
D.明了
参考答案:C
My mother wants me the milk every day. She says it’s good
my health.
A. to have; to B. to drink; for C. drink; for
焊缝探伤所用的阵列探头分段扫查间隔应≤15mm。