Definition: You are given a conversation between two people. 'Person1:' and 'Person2:' are used to separate their respective dialogues. You are required to assign a label 'formal' if there is an absence of emotion and a presence of questions anywhere within the conversation. If such pattern is not found assign the label 'informal'.
Input:  Person1:       There is a tornado warning on . My mother just told me she heard it on the radio .  
 Person2:What is a tornado warning ?  
 Person1:        It means that a tornado has been seen somewhere in the area .  
 Person2:Really ? In New Berlin ?  
 Person1:        No . Not necessarily in town . But in southern Wisconsin somewhere . A tornado has been spotted . They have two stages here.This is what is called a " tornado watch . " That means that the weather conditions are perfect for a tornado .  
 Person2:I understand . They think a tornado might come .  
 Person1:        Yes . People should look out , because maybe there will be tornadoes coming.So it's called a " watch . "  
 Person2:And the second stage is called a " tornado warning " .  
 Person1:        Yes . If a tornado has been spotted , they announce a " tornado warning " . So if there's a tornado warning on , it means a tornado is out there somewhere .  
 Person2:It's scary .  
 Person1:        Well . Tornadoes can be dangerous , it's true.If we hear something like a loud train coming , then we have to go in the basement .  
 Person2:What do you mean " a loud train " ?  
 Person1:        That is what tornadoes sound like . They sound like trains . They're very loud .  
 Person2:But if you hear them coming , isn't it already too late ?  
 Person1:        Maybe . It depends on the tornado.Some can move across the ground at 200 miles an hour.That is very fast . Others aren't so fast .  
 Person2:Have you seen a lot of them ?  
 Person1:        I've only seen one in my life . I was looking out the window . It was around two miles away . It was very interesting to watch.But it was heading toward my friend's house . So I quickly called them on the phone .  
 Person2:Did it hit their house ?  
 Person1:        No , it didn't . But they are glad I called them .  
 Person2:What were they doing when you called ?  
 Person1:        They were all sitting in the living room watching TV.They had no idea a tornado was coming toward their house.If it had hit them , they could have all been killed .  
 Person2:That's terrible . Do many people die in tornadoes ?  
 Person1:        Not so many really . But a lot of houses are destroyed sometimes . 

informal