Question

---Hi, Tom. Any idea where Jane is?
---She ______ in the classroom. I saw her there just now.

1. A.
   shall be
2. B.
   should have been
3. C.
   must be
4. D.
   might have been

Answer 1

C
考查情态动词表推测的用法。句意为：——你好，汤姆。知道简在哪里吗？——她一定在教室里，我刚才看见她在那里。B项和D项表示对过去事情的推测，shall be则表示将来。故选c。