Question

The professor ______ to walk out of the office when one of his students came in.

1. A.
   was about to
2. B.
   was going to
3. C.
   would
4. D.
   was to

Answer 1

A
考察固定句式be about to，将要做某事。句意：当他的一位学生进来时，这位教授即将走出他的办公室。选项BCD缺少谓语动词，故选A。