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: How was your trip to America ?
Person2:We had a fantastic time .
Person1: Did you go to the Magic Kingdom ?
Person2:No , but we went to the Kennedy Center .
Output:
informal