The question asked no longer makes any sense in the current environment.

Google and all other major search engines like Yahoo, Bing have disqualified the Meta keyword tag long before.

So even if you're adding the meta keyword tag in your webpages, Google and all other search engines are never going to take a look at that meta and you are never going to get any SEO benefit out of it.

So it's better to concentrate on Title, Description, Body content of the webpage to make SEO work for you.