MGJIM

I want to block certain ads - Like Adsense from certain pages. This can be done at the ad level with delivery option site url: does not contain ... then ad a word. So maybe I have an ad for dogs that I do not want on a cat page -- or do not want adsnse to run on pages that have the word youtube. Etc. My question is can I sperate the blocked pages with commas? Or do I have to make an instance for each word? Also, is there a way to do that at the campaign level as opposed to the ad level?