问题补充：
-----“Shes not a dancing teacher, is she?”
------ “.”
A. Yes, and she isn
B. Yes, but she was
C. No, but she isn
D. No, but she was
答案：
A. Yes, and she isn
B. Yes, but she was
C. No, but she isn
D. No, but she was
解析：
可视为No, she isn . But she was a dancing teacher.之省略，即其意为“她现在不是舞蹈教师，但她过去是”。此题也可以这样回答：No, but she used to be.
