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:       When will our party be held ?  
 Person2:Next Wednesday .  
 Person1:        Have you sent out invitations by our party ?  
 Person2:Yes , I have .  
 Person1:        When ?  
 Person2:Ten days ago .  
 Person1:        Could Dr.Cole like to attend the party ?  
 Person2:Yes , he will .  
 Person1:        That's fine . 

informal