There is a difference between the words QUIET (meaning calm: the horse is a quiet horse) and QUITE (completely, wholly, or entirely: quite the reverse; not quite finished).
When a male horse has been surgically altered so as not to be able to breed (it is no longer a stallion), it has been gelded, not guelded.
You’ve reduced the price, not reused or redused.
A horse is, or can be registered, it is not registerd.
You are mounting a horse, not mouting a horse.
You have been riding a horse, not ridding a horse.
It is purebred not pure bread.
And, from a fantastic blogger, The Oatmeal: