问题补充：
While Helen the guitar, her mother came in.
A. was playing
B. is playing
C. played
D. plays
答案：
(答案→)A. was playing
B. is playing
C. played
D. plays
解析：while引导时间状语从句，常用进行时态。
如果觉得《While Helen the guitar her mother came in.A. was playingB. is playingC. playedD. plays》对你有帮助，请点赞、收藏，并留下你的观点哦！
