高考书面表达怎样运用复杂结构和高级词汇

②If you come back before 6:00, you can go out.(一般) You can go out on condition that(provided that) you come back before 6:00.(高级) ③If she doesn’t agree, what shall we do?(一般) Supposing that she doesn’t agree, what shall we do?(高级) 九、使用虚拟语气