Given the task definition and input, reply with output. 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: Why are those people crying ?
Person2:They must have just come back from tomb sweeping because today is Tomb Sweeping Day .
Person1: Tomb Sweeping Day ? What is it ?
Person2:Tomb Sweeping Day is a traditional festival in China , on which many Chinese mourn the dead .
Person1: What do they do ?
Person2:People go to the cemetery to pay their respects to the dead .
formal