问题补充：
— Can you sing this song in English?
— Of course I can. It often by us kids.
A. is; singing
B. does; sing
C. has; sung
D. is; sung
答案：
A. is; singing
B. does; sing
C. has; sung
(答案→)D. is; sung
解析：句意：--你能用英语唱这首歌吗？--当然我能。在我们小时候它就经常被唱。分析考查被动词态的用法。句中often体现为一般现在时的被动语态。 故选D
