not untill的时态
问题描述:
not untill的时态
答
not ...until 引导时间状语从句,从句不能用将来时,主句是一般将来时,从句用现在时.Don't get off the bus until it stops.(主句是祈使句从句用现在时)He didn't go to bed until his mother came back.(主句是过去...