问题
选择题
After ______ was about then minutes, the teacher gave the students the correct answer to the question.
A．what
B．that
C．it
D．which
答案
答案：A
考查宾语从句。句中After是介词，后面是宾语从句，且从句______ was about then minutes缺少主语，所以用what引导，选A。