We can't really give you a simple "do this" answer - there is far, far too much other stuff involved that we don't know about. For example, are your responses fixed? Do you have the capability to vary them according to the user input? For example if the user says "the ball is green", can you pick out the "ball" and "green" as significant, and slot them into a random stock phrase:
"Can you see the {1} {0}?"
"The {0} looks {1} to me as well!"If you can, then you need to look at this one way, if not, than you need to look at it another.
Random phrases are easy: just have an array of phrases and pick one at random:
Private rand As New Random()
Private responses As String() = New String() {"..", "..", ...}
...
Dim response As String = responses(rand.[Next](responses.Length))
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How to Build Eliza Chatterbot - A Program that can Chat with Humans[
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