Detailed Instructions: 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'.
Q:  Person1:       Bob , how about joining the boxing club this summer vacation ? 
 Person2:What a good idea ! 
 Person1:        So let's get registered tomorrow . 
 Person2:OK . 
A:
informal