问题
选择题
—Does Li Ping serve in the army?
—No, but he ________ in the army for five years.
A．served
B．has served
C．is serving
D．would serve
答案
A
由答语No可知他现在不在部队服役，是以前“服过役”，故用一般过去时。千万不要被时时状语for three years所迷惑，而错选答案B。