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 will you do now ? Propose to her .  
 Person2:Of course I won't chill out . Opportunity knocks only once .  
 Person1:        You should strike while the iron is hot .  
 Person2:You're right . I will have a talk to her about that . 

formal