answer: Les and #Person1# are choosing a birthday gift for Grace. They consider cat food, a book, some sweets, and flowers. Then they decide on a plant.
documents: #Person1#: Where are you going, Les?
  #Person2#: To the pet shop. I want to buy some cat food for Grace's birthday. She loves her cats and I'm sure she'd like to get some cat food.
  #Person1#: But it's Grace's birthday, not her cats'. She enjoys reading. Let's get her a book.
  #Person2#: OK. Let's go to the book shop then.
  #Person1#: I prefer shopping online. It's easier.
  #Person2#: OK. Let's use dad's computer. How about this book on cats. It seems to be interesting. It is only $6.00.
  #Person1#: That's quite cheap. But she has that book already. Mom gave it to her for Christmas remember?
  #Person2#: OK. Not this book. What then? Some sweets?
  #Person1#: It's not your birthday. Grace really dislikes eating sweet things and she wants to lose weight.
  #Person2#: I know what, she loves flowers. Let's get her some.
  #Person1#: Flowers don't last. I prefer to give presents that last. Let's get her a plant then.
  #Person2#: I'd love to give her that. Let's check some pages for plants.