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'.
Input: Person1: That's brilliant ! We can name the grades of motor oil by where they come from .
Person2:Mr . Mechanic , I'd like a nice Venezuelan blend this morning .
Person1: I think the Saudi Arabian will hit the spot today .
Person2:But really , maybe this can work . Everyone loves coffee , and everyone needs motor oil .
Person1: A match made in heaven .
Output:
informal