改错 At a time,some of our classmates were lost in playing computer games.
问题描述：
改错 At a time,some of our classmates were lost in playing computer games.
答
a --> one
答
At one time 曾一度
这样就和后面的 were lost in.时间一致了
请及时采纳,不懂继续问( 天天在线 ）