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: Hong , I really need to call back to the UK but I can ' t afford to pay for the roaming charges .
Person2:Well , why don ' t you use a local SIM card ?
Person1: Can I do that ?
Person2:Yes . Just go to the convenience store and ask for a SIM card . Then insert it into your phone .
Person1: I see . How much will that cost ?
Person2:Well it ' s 100 RIB for the SIM card then it will cost you about 10 RIB per minute to call the UK .
Person1: Wow , that is cheap . Thank you very much .
Output:
informal