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:       Can you take part in our picnic this Saturday ?  
 Person2:That would be fine . Where are you going ?  
 Person1:        We plan to go to a forest in the suburb . There is a beautiful river there . We can do some fishing .  
 Person2:Great .  
 Person1:        And don't forget your fishing tackle .  
 Person2:Ok . I like fishing very much . 

informal