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:       Welcome , Mr . Sun .  
 Person2:Thank you for your entertaining me .  
 Person1:        Today I'll invite you to enjoy the seafood.Please make yourself at home .  
 Person2:Excuse me , what business are you looking after in Germany ?  
 Person1:        I am running Chinese arts and crafts .  
 Person2:What arts and crafts are you interested in this time ?  
 Person1:        I hope to import some silk from Hangzhou to Germany . Can you help me ?  
 Person2:Sure , I'll certainly help you do it . 

formal