With regards to Broad Negative, for single keywords, what if you had -widget as a negative and somebody used Widgets in the search? Does Negative Broad definately include all plurals of keywords in this scenario or would one need: -widget -widgets in their account?
As far as I can see, negative Broad Match doesn't use expanded matching and so would not expand 'widget' to cover 'widgets'. Therefore you would need to use both: -widget -widgets
For some of the keywords you will find the plural words draw more search results, I think as suggested by Prodrock , it's better to optimize for both.
Google does allow broad, phrase and exact match for negative keywords. They also suggest you add the plurals if you wish to target them. See below for further information. https://adwords.google.com/support/...tive+matched+keywords&topic=&type=f& onclick= cheers, Anthony Buchalka