Agree with berrywoo.
Dr. O.
Let me elaborate: if her RX of lenses and measurements: base curve, diameter, refractive power, is different than your lenses won't fit her!
If you choose to give her a pair, make sure they're brand new and don't bother asking for them back. They won't do you any good anymore as they've been worn by someone else and if you insert the one she wore into your own eyes then you could get a serious infection.