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:       Would you like to go sightseeing tomorrow ?  
 Person2:Not a bad idea .  
 Person1:        What would you like to see in Beijing ?  
 Person2:Well , let ’ s see . I ’ d like to go to see the Summer Palace .  
 Person1:        I ’ ll pick you up here tomorrow . 

formal