—What were you doing when he “hello”to you?—I in front of the blackboard.A. was saying; re

问题补充：

—What were you doing when he “hello”to you?

—I in front of the blackboard.

A. was saying; read

B. was saying; was reading

C. said; read

D. said; was reading

答案：

A. was saying; read

B. was saying; was reading

C. said; read

(答案→)D. said; was reading

解析：句意：当他跟你打招呼时你在做什么？我正在黑板前读书。根据主句的时态为过去进行时可知When引导的时间状语从句用一般过去时，回答用过去进行时；故选D。