W - Why don't you try these tips:
 
1. Noguchi's idea of having the student make a tag or yes/no question to force
them to locate the verb.  If it's a run-on or comma splice, this student will
have difficulty making the question because there will be 2 (or more) verbs to
choose from.
 
2. Have HER write a definition of a sentence/run-on/comma splice.  Starting
from students own concept about a grammatical term is more instructive (to both
you and them) than giving them a definition that may not make sense to them
unless they already understand it.  (Clear Only If Known - COIK factor).
 
I'm writing a paper on this approach that is being piloted now.  Let me know if
you have success with either of these.
 
Nancy Burkhalter
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