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:       After probation , you'll find that our silk products feels more comfortable than others . 
 Person2:How about this product selling from last month on ? 
 Person1:        It's selling like hot cakes , and we have lots of regulars now . Would you like to place a trial order ? 
 Person2:Am . Well , can I have a try of the sample free of charge ? 
 Person1:        Yes , we have the free samples for customers . And you can have a try . 
 Person2:Thank you . We'll order once we try the sample . 
 Person1:        Please wait a moment and fill out the order form . And we'll send you our sample . 
 Person2:OK . 

formal