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:       Could you tell me how to use the washer and dryer ? 
 Person2:What do you need help with ? 
 Person1:        Do you know how to turn them on ? 
 Person2:Do you have any change ? 
 Person1:        I need change for the machines ? 
 Person2:You need to put 50 cents into the washer machine and a dollar into the dryer . 
 Person1:        So what do I need to do ? 
 Person2:The machines will turn on once you put the quarters into the slot . 
 Person1:        That's really all I have to do ? 
 Person2:That's everything . 
 Person1:        Thanks for all your help . 
 Person2:I'm here if you need any more help . 

informal