Hi There,
I am a SAHM with 3 children ages 4,7 and 10. From what I have experienced personally, and with friends,children tend to bite when they feel frustrated by not being able to communicate what they are experiencing. Perhaps you could be her "shadow", and find out what happens just prior to her biting. Then you can help her use a word to express the frustration she is feeling, and demonstrate the proper way to handle the frustration. Taking turns, redirecting her etc. Example if another child is taking a toy, that she just had her eye on, you may want to say something like "I know,that really makes me sad too, when I want something and can't have it, but we have to take turns, and use our big girl words, we don't bite when we are sad or angry" help her apologize to the other child, and then redirect her to another toy. Later when it is just the two of you, tell her how she should be proud of herself for being such a big girl and using her words. Keep reinforcing the use of using words to express her frustration, and let her no it is ok to have the feelings, but not to act on them by biting. That may help. Good Luck to you!