Zebras are easy to sex however society finches or bengalese finches can be a little more difficult.
Well you have one of each,,,so yes they can,,,this is what i would do...be smart .read up on yahoo.com (breeding finches) learn all you can if you want to breed ...if not just toss the eggs away..its a full time job as you will see. and will cost you money for the breeding of your young birds,,,good luck
About 3-4 months ago I got a Society Finch named Mr.F( Arrested Development joke) .So today I finally got Mr.F a much bigger cage and to give him some company I also got a Zebra Finch today.Now when I asked the guy at petsmart he said the Zebra was a male so I trusted what he said paid for the cage and the bird. 1 hour later I'm googling info on Zebra finches and find out the one I got is actually a female(thanks petsmart guy) . So now my concern is will they mate, will their offspring be healthy if they do?