Definition: 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:       It seldom rains this summer . 
 Person2:Yeah , some places are very short of water . 
 Person1:        Because of pollution and other things , our environment has become worse and worse . 
 Person2:You see , . This time I traveled to the West . When I looked out of the windows of the rain , all the lands that I could see are as dry as a bone . 
 Person1:        It is serious . 

informal