Question

---How often do you visit your father in the village?    
---I feel ashamed．Just__________．

1. A.
   often
2. B.
   by accident
3. C.
   once in a while
4. D.
   all of a sudden

Answer 1

C
时间副词辨析。Often经常，常常；by accident偶然，意外的；once in a while 偶尔，有时；all of a sudden突然地，出乎意料的。句意：你多久拜访一次你农村的父亲？不好意思。只是偶尔。结合语境可知选C。