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'.

Example Input: Person1: Good to see you . Come on in .
Person2:Thank you . Here's a present for you .
Person1: Oh , you shouldn't . But thank you very much .
Example Output: informal

Example Input: Person1: Excuse me , I'm a little lost . Which bus do I take to get to Shi Da ?
Person2:Let's see . From here , you have to take the 278bus .
Person1: Oh ok , where do I get off ?
Person2:You should get off at the first Shi Da stop .
Person1: Ok , thanks ...
Person2:You're new at this , huh ?
Person1: No , is it difficult ?
Person2:No , it's quite simple . When you get on , just ask the bus driver when to pay the fare and where you want to get off .
Person1: How much does it cost ?
Person2:Only 15 NT per section . Oh look , that is your bus .
Person1: Wow , I can't thank you enough .
Person2:Don't mention it .
Example Output: informal

Example Input: Person1: I'll talk to you later .
Person2:What's the rush ?
Person1: I have to get off the phone now .
Person2:I'm not ready to get off the phone with you .
Person1: There are other things I need to take care of .
Person2:What is it that you need to do ?
Person1: Please don't be nosey .
Person2:I'm not being nosey , it's just a question .
Person1: You don't need to worry about that .
Person2:That was mean to say .
Person1: I am very sorry , but I must go .
Person2:I guess .
Example Output:
formal