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:       What's the weather like ? 
 Person2:I don't know . I just woke up . 
 Person1:        Why don't you look outside ? 
 Person2:Okay . It looks like rain . 
 Person1:        Why do you say that ? 
 Person2:The sky is gray . 
 Person1:        Is it raining right now ? 
 Person2:No . 
 Person1:        How do you know ? 
 Person2:The street isn't wet . 
 Person1:        I have to go shopping today . 
 Person2:You'd better take an umbrella . 

formal