按要求改写句子。

1．女服务员把一大束五彩缤纷的花捧到她的面前。

    “被”字句：                                                                                                        

2．难道不应该给黯然无光的失败者献花吗？

     陈述句：                                                                                                              

3．燕子是鸟类著名的建筑师。 

    否定句：                                                                                                                

    双重否定句：