I remember when my girls were about 4 and 5 they had a friend sleeping over. This little girl swore like a trooper.

A few days later I heard my girls swear when they were sitting in the bath. I made them both stand up and slapped their bum and told them never to use that word again (F-word). I told them that it was a bad word and that we wouldn't  allow swearing.

They didn't know what it meant at that time, they had just copied the other little girl, but they got the message.

My kids never swore again as long as they were in primary school as far as I'm aware. We hardly ever swore and especially never within earshot of the kids.

When they went to secondary school they sometimes let one slip and were always told off for it. It was rare though that they swore in front of us. Now, what they did outside I could not control. They were influenced by peers as they got older who did swear a lot. Not much you can do about that, except keep telling them off when you hear them talking and swearing to their mates. We even told their mates off when they did. And after a while they all knew not to swear when they were at our house.

My girls (22 and 24)  now tell the little kids in our neighbourhood off when they hear them swear.

So although I believe parents have the greatest influence on their children's behaviour, the community and the teachers have to help as well. We can't be with our kids 24/7. But we can all do our bit.