首先你这个题目是有问题的：I will visiting the world Expo in shanghai this summer,这句话里,will后面是要直接跟动词原形visit的
感觉楼主应该是初中的吧,所以故意没有用很多语法：
TOM:hello what are you going to do during summer holiday,Wendy?
Wendy：er,I’m going to visit the world expo in shanghai.
Tom:wow,that’s great!Do you have the ticket?
Wendy:yes,my father bought three tickets for the three of us—my father,my mother and me.
Tom:so you are going there with your car?
Wendy:no.because we are going to stay in shanghai for more than a week,so driving our own car is not convenient.
Tom:yeah,that’s correct.I hope my father can also take me to the expo for a visit,too.
Wendy:maybe you should ask him,and I think he will agree.
Tom:that’s what I want to do this night.
Wendy:so,good luck.Bye~
Tom:thank you,bye~