Just now,I have a quarrel with one of my best friends,She is a very precious friend,though she always ununderstandable.I don`t wanna lose our friendship,can you tell me what can I do?

Why don't you start by telling her how precious her friendship is, but that perhaps you misunderstood something that caused you to quarrel. It's certainly easy to do if she is difficult to understand. Ask her if you can't just agree to disagree. That's what good friends do all the time. People who always agree on everything soon get bored. Anyhow, Welcome to AnswerPool.

Tell her exactly what you told us. "You are a precious and understanding friend, and I do not want to lose our friendship over our quarrel."

Thank you!Now I know what should I do.I am sure I can succeed.