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 any evening bus tour ?  
 Person2:Yes , we have . The city is famous for its beautiful evening scenery .  
 Person1:        I have heard of that before . When shall we start ?  
 Person2:It starts at 7:00 and lasts 3 hours . 

formal