Regexp help second

Hi! Last help about regexp solve my problem, but I have another one. I've made some regexp but it does not work always Let say I have some strings 1) this is some domain.com test 2) domain.com I can make this work either for first example of fo second, but not for both. What I want is replace of domain.com to get this is dome domain.com domain com test so replace should be \1 \2 \3 so for second example I did /((.+)\.{1}(.+))/ How can I extend this to work in both. regards Uros