按要求改写句子。

1．老师正在绘声绘色地讲雷锋叔叔的故事。 

     缩句：                                                                                                             

2．张宏是少先队员。

     扩句：                                                                                                             

3．我不干活怎么能白吃您的饭呢？

     陈述句：                                                                                                          

4．海上日出是伟大奇观。

    反问句：                                                                                                          

VEP在眼科临床中的应用。