She said she wanted to give me a Chinese lesson if I bought her something to drink. It's a common scam--the "Teahouse Scam"--where you get stuck with a huge bill and are intimidated into paying. (Don't pay. They don't want police involvement.)
"How about we sit in the park instead," I say. "Trade one English lesson for one Chinese lesson?"
"No! I don't need English lesson! My English is enough good!"