Definition: You are given a conversation between two people. 'Person1:' and 'Person2:' are used to separate their respective dialogues. If the conversation begins with a question, label it '1' otherwise '0'.
Input:  Person1:     Now let's begin the class . Who is on duty today ?  
 Person2:  I am , sir .  
 Person1:      Please come to the front to have five minutes ’ free talk in English . Very well ! Whose turn is it to have a free talk ?  
 Person2:  It's me , sir . But I am sorry I have forgotten to prepare for it .  
 Person1:      Well . Don't forget to perform your duty next time , ok ? Now , let's start our lesson . 

1