Is it even possible to extract domain/TLD from URL using Grep

for example ... please see the image at
yfrog.com/n3grep1p

I am trying to extract the domain name (TLD)
getrichslowly.org
43folders.com
chatbots.org
bilinkis.com
getrichslowly.org
freelanceswitch.com
getrichslowly.org


So far I managed to
cat linkreport3.csv | grep -E -o "([0-9,a-z\.-]+)\.([a-z]{2,6})"

... please see the image at
yfrog.com/2tgrep2p

I just need the tlds !

Thanks for any help

Sorry I am not allowed to post urls !