flew off of her feet vs flew off her feet

[vectra]

Hello,

I am more used to saying 'she flew off her feet', but a few minutes ago I came across this sentence: 'Manhattan prosecutors said in court papers that Fuller hit Rosas "with so much force that the woman flew off of her feet, was knocked unconscious and hit her head on the ground."

Which one sounds more natural - flew off of her feet or flew off her feet?
Are these two expressions interchangeable?

Thank you in advance.

[paul.moss]

The second is correct too; it's got an informal flavour to it though!

[The Dude]

I agree with paul.moss that the second (off) is correct, but would say that the first (off of) definitely is not. 'She flew off her feet' does have an odd sound to it, making me think of Mary Poppins, so I'd suggest 'she was knocked off her feet' as sounding more natural .

Adding 'of' after 'off' is nonsense - some people do say it, but only through ignorance.