Question

一Mary，you look confused．Have you made sense of the passage we are talking about?
一Yes，I      another problem just now

1. A.
   have thought of
2. B.
   was thinking of
3. C.
   thought of
4. D.
   had thought of

Answer 1

B
“玛丽，你看起来有点迷惑，你没有弄懂我们刚才讨论的那一段吗？”“是的，我刚才正想别的问题。”根据句意选择D。