diff --git a/factorOperations.py b/factorOperations.py
index 1519c87..509ef39 100644
--- a/factorOperations.py
+++ b/factorOperations.py
@@ -199,6 +199,8 @@ def eliminateWithCallTracking(callTrackingList=None):
 
         new_factor = Factor(unconditioned_variables, conditioned_variables, variable_domains_dict)
 
+        # we need to reconstruct the probability tables for the new factor
+        # need to remove the elimination variable, so we should add all probabilities with the same elimination variable.
         for fill_assignment in new_factor.getAllPossibleAssignmentDicts():
             prob = 0
             eliminate_variable_domains = factor.variableDomainsDict()[eliminationVariable]