I'm not going to scold my 7 year old for swearing.
Why would you let them talk like that?
I don't like to be too strict with the little ones.
There are some words that aren't acceptable for a child to use. As a parent, you are responsible for your children, and need to teach them right from wrong. You should teach them good manners, and give them a safe alternative to swearing, like "Oh rats!" or "Oh, phooey"
I will not punish her for her foul language. No child needs to be punished for a harmless slip up.
I am not saying that you need to punish them, but you still need to teach them right from wrong. There are times and places where swearing is not socially acceptable. Children will learn easily what is appropriate to say from your own example. Teach them new, safe words to express their feelings.