answer: It's #Person2#'s turn to give a free talk but #Person2# forgets. The teacher asks #Person2# to do it next time.
documents: #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.