简述操作技能的培训要求。
参考答案:(1)准确地示范与讲解; (2)必要而适当的练习; (3)充分而有效的反馈; (4)建立稳定清晰的动觉。
The lazy boy _____there doing nothing all the afternoon, but he______ to his boss that he had finished what should be done.
A.lay; lied
B.lied; lying
C.laid; lay
D.lying; laid
营养强化