Not sure I understand what you are doing, but glad to hear you have it working.
To exclude a value or relationship from a variable you can use "exclude"
exclude #instantiation from #verb;
One thing that looks odd in your script is,
assign #word to :word1;
#word is a primitive, not a variable, assign should only be used with variables.
My guess on your corruption is that you somehow corrupted the global :input :speaker or :sentence variables, such that they no longer match. We should be preventing users from changing these, but are not currently doing so. You can check if they have been corrupted from the knowledge browser by browsing "input-varaible" (this is the global :input).