--Dose Liu Hui serve in the army?--No,but he ( ) in the army for three years.A served B has served C is aerving D would serve

--Dose Liu Hui serve in the army?--No,but he ( ) in the army for three years.A served B has served C is aerving D would serve
--Dose Liu Hui serve in the army?
--No,but he ( ) in the army for three years.
A served B has served C is aerving D would serve

--Dose Liu Hui serve in the army?--No,but he ( ) in the army for three years.A served B has served C is aerving D would serve
选A
--Dose Liu Hui serve in the army?
既然回答的是NO,说明他现在已经不在部队了,不可能用现在完成时,因为现在完成时表示持续到现在的意思,应选A

B现在完成时 用has been的形式

A

选B，

B for three years就是现在完成时的标志，所以选B