only的倒装句举例：
当only修饰的副词，介词短语，状语从句放在句首时要用倒装结构。例句：
1.Only then did the man realised how much damage had been caused.
只有到那时那个人才意识到他引起了多少伤害。
2.Only by plane were we able to get to Shanghai ahead of time.
只有乘飞机我们才能提前到达上海。
3.Only after he helped me was I able to finish the task in time.
只有他帮助了我，我才能及时完成任务。
