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:       I think that the company retreat should be in the mountains this year .  
 Person2:What a great idea !  
 Person1:        January would be a good month for a mountain retreat .  
 Person2:I like the mountain idea , but I am not so sure about the month of January .  
 Person1:        You know , now that I think about it , you might be right .  
 Person2:April might be nice . It is far enough away to make the necessary arrangements .  
 Person1:        That is a good suggestion .  
 Person2:We could ask everyone what would be the best time for them .  
 Person1:        Yeah , that would let us know what would work best .  
 Person2:I'll put the survey online this afternoon . 

informal