You will be given a definition of a task first, then some input of the task.
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'.

Person1: David , what have you been up to lately ?
Person2:I went on a trip with my family last week .
Person1: Really ? Where did you go ?
Person2:We went to Europe .
Person1: What cities did you go to ?
Person2:London , Paris and a few other cities .
Person1: Did you go to Berlin ?
Person2:No , We didn't go there . I'd like to go there next time .
Person1: I think this summer is a good time to visit Berlin . It's a beautiful place and the people there are very nice .
Person2:That's what I've heard .
Person1: I went there last year . If you want , I can give you some information I have about the city .
Person2:Thanks .
Output:
informal