问题补充:
这句话的主句和从句怎么分,这里是that引导从句还是who引导.The first person who opens that door will get a shock.这里的that有什么用为什么不改成opens the door.主句从哪里到哪里从句从哪里到哪里.
答案:
the first person will get a shock 是主句,who opens that door 为定语从句.是who 引导的定语从句,这里的that 不是引导词,是指那扇门,不能用the 希望对你有用.