问题
选择题
-- Did you visit your grandparents yesterday?
--Yes, and when I got there, they _____ in the fields .
A．worked
B．have worked
C．were working
D．had worked
答案
答案：C
题目分析：句意：--昨天你去看祖父母了吗？--是的，当我到达那里的时候，他们正在田里干活。时间状语是when I got there,说明是在过去某个时间正在做…，符合过去进行时的用法，选C。
