Detailed Instructions: 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'.
Problem: Person1: Let's meet tonight at the Thai restaurant at about 5 .
Person2:Fine , I'll take a taxi .
Person1: Why don't you walk ? It's only about 20 minutes walking and it's a nice evening .
Person2:Never thought about it , I sure you are right . It's quite a short walk .
Person1: Ha-ha , see you then .
Solution:
informal