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:       It's too hot to read .  
 Person2:We'd better go out for a walk .  
 Person1:        Which season do you like best ?  
 Person2:Spring .  
 Person1:        How about summer ?  
 Person2:I dislike it most .  
 Person1:        Why ?  
 Person2:Because the hottest season is summer in a year .  
 Person1:        But sometimes summer is more charming than the other seasons . 

informal