---Yourgrandfatherstillseemsveryenergetic,althoughheisa...

問題詳情：

---Your grandfather still seems very energetic, although he is already in his seventies now.

---Yes, he _______in the army for three years when he was young.

A． would serve             B． served

C． had served               D． has served

【回答】

B

知識點：動詞時態與語態

題型：選擇題