user_query: delete grapes from list
response_text: I couldn't find grapes.
user_query: add grapes to my recipe list
response_text: Alright, I added grapes.
user_query: add grapes to my list
response_text: OK. Which list do you want to add to?
User: Please note that I exercised for 30 minutes.
Parse: Log_exercise ( duration « 30 minutes » )