He did not leave his office until he had finished work这里从句为何用过去完成时?

相关推荐

• 用所给词正确的时态填空 1.After he had read the book ,he ____ (write) a review of it .2.He did not leave his office until he ____ (finish) work .3.If he ____ (break) his promise ,I'll never speak to him again .4.If the weather is fine ,we ____ (go) for a picnic .
• He did not leave his office until he had finished work这里从句为何用过去完成时?
• He did not leave his office until he had finished work这里从句为何用过去完成时?
• I didn't leave the office until I finished ma work.同义句 I_____the office_____I finished my work
• He didn't leave his office an hour ago.（改为肯定句）～