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:       Have you met John ? 
 Person2:Yeah , he came back from America last week . 
 Person1:        Have you noticed how fluently he speaks English ? He has only lived in America for less than three months . 
 Person2:He must have a good ear . 

formal