answer: #Person1# invites #Person2# to go shopping on Sunday but #Person2# has to help #Person2#'s brother's English in the morning. #Person1# suggests that they go in the afternoon.
documents: #Person1#: Would you like to go shopping with me on Sunday?
  #Person2#: I'd like to, but I have to help my brother's English in the morning.
  #Person1#: I did not mean morning or afternoon.
  #Person2#: Oh. That's great. Then it is a different thing now.