when did he leave th classroom?he left __ you turned back to——when did he leave th classroom?——he left __ you turned back to write on the blackboard.A.the time B.until C.the minute D.before

when did he leave th classroom?he left __ you turned back to——when did he leave th classroom?——he left __ you turned back to write on the blackboard.A.the time B.until C.the minute D.before
when did he leave th classroom?he left __ you turned back to
——when did he leave th classroom?
——he left __ you turned back to write on the blackboard.
A.the time B.until C.the minute D.before

when did he leave th classroom?he left __ you turned back to——when did he leave th classroom?——he left __ you turned back to write on the blackboard.A.the time B.until C.the minute D.before
选C,问句的意思是,他什么时候离开教室的?按照逻辑应是当你转过身在黑板上写字之后离开的,C选项有这一刻的意思,整句翻译是他在你转过身在黑板上写字之后的那一刹那离开的.

abc都可以的。ac意思相同，全部代表瞬间动作发生时，并且在语法上是有缩略介词这种方法，但时间状语一般都是提前的。不过不能算错误。意思为你一转身他就走了
而b则是口语行为。理论上老师是要否定回答做肯定的。意思为你转身后他才走的

AB C

d