小练笔。    

        结合课文内容，分别写出人物的特点，不超过50字。   

诸葛亮：                                                                                                                                      

周瑜：                                                                                                                                         

曹操：                                                                                                                                          

简述王安石变法的背景、主要内容及其实质意义。