fall down Intransitive Meaning: fall to the ground Example: I was walking down the street when suddenly I fell down.
There is a popular television show in the United States called “Wipeout” where people try to complete obstacle courses without falling down. It’s quite amusing to watch their efforts: http://www.youtube.com/watch?v=obHBoaQKCsc
wipe out Intransitive Meaning: fall to the ground unexpectedly and roughly Example: I wiped out on the banana peel as I was walking down the street!