THEM: i would like 2 books and 1 hat  YOU: i can give you 2 books, but no hat. i'd like 1 book and 2 balls. deal?  THEM: no - i will settle for hat and 1 book  YOU: no can do on the hat. you can have everything but the hat.  THEM: the hat is a must for me.  YOU: sorry, it's a must for me as well. i guess we have to select no deal was agreed.  THEM: guess so - when it's available  YOU: ok  THEM: i don't know when it appears  YOU: neither do i.