Reece, your code is common knowledge, I've made something like that before that used arrays to determine outputs. Some suggestions: use upper$() to make sure you get what the user is typing, strings are case sensitive. Make sure you spell your intended inputs properly, you aren't as bad as some people, but lawyers ('loya') and chefs won't get a response.
It's quite hard to determine what the user is saying and produce a reasonable response every time. You could use augmenting external arrays to hold resonses, but that would be quite hard.
Gunloader, how good were your parsers? Mine only ever detected two word sentences, verb and object.