When I moved out this always worked well for me:

"I don't know your situation but I know that if I don't ask it will bother me all day. My name is Yeildo."

I got a lot of dates using this. I'd make sure I was looking her right in the eye and not getting too close.

I never had a woman get mad at me and several gave variations of "I'm in a relationship but thanks for asking." When I got this I stopped trying to get a date.

In a bar, if she was friendly, I would say "Ok, you have to find me a date." And many times they would!

But if you are staring at her chest..... you have no chance. Be a gentleman.