以下关于IP数据报报头各域的描述中，错误的是______。A．报头长度域是以32位的

最近，洛阳小伙扶摔倒老人被讹一事引起了社会的广泛关注，人们都在议论还该不该去做好事，帮助他人。而“Positive Energy”一词早已对我们中国人产生了很大影响，因此，很多人并不会因此就不去做好事了。瞧！你身边就有很多助人为乐的同学，他们的事例值得我们学习。请根据下面表格信息给学校校刊写一篇短文，谈谈身边的好人好事，号召大家向他们学习。词数60—80（开头和结尾已给出，不计入总词数）

Who they are	What they usually do to help others
Liu Chang	make our school beautiful (clean the classroom..)
Li Bing	help other students with their studies…
Zhang Ling	help the people in trouble (cheer others up…)
…	…

Dear Editor,
In our school,some students are always thinking more of others and ready to help them.I am moved deeply.Here is what they usually do.
Liu Chang is a very good student.                                                             
                                                                                            
                                                                                            
                                                                                            
                                                                                            
                                                                                            
                                                                                            
                                                                   
I hope everyone can learn from them and do something for others.
Yours, 
Mark