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: Are you ready to order , sir ?
Person2:What's the special here ?
Person1: We have steamed chicken , braised pork and Beijing roast duck and so on . Here's the menu . What would you like to have ?
Person2:Well , let's try some braised pork , sweet and sour fish and some fried beans .
Person1: Would you like anything to drink ?
Person2:Just some soft drinks and only a bottle of beer .
Person1: All right . Wait for a moment , please .
Output:
informal