answer: #Person1# helps #Person2# to change the shoes from black 42-sized to brown 43-sized without extra pay.
documents: #Person1#: What can I do for you? We have many new introduced choose to choose from.
  #Person2#: Sorry I bought a pair of shoes with the size of 42 for my husband, but it's a little tight for him.
  #Person1#: OK. Show me your receipt and you can change a larger size.
  #Person2#: I have to change one pair with the size of 43?
  #Person1#: Here you are. Is this perfect for him?
  #Person2#: Yes, and he would like brown rather than black to match his suit.
  #Person1#: I see. Here are the brown shoes with the right size.
  #Person2#: Thanks! Need I pay for extra money for the larger shoes?
  #Person1#: You needn't if you still choose shoes with the same brand.