祈使句的反意疑问句
1.祈使句的反意疑问部分为肯定形式,要用shall,will.如:
    Pass me the book,will you?
2.Let’s表示第一人称的祈使句,反意疑问句为“Shall we?”.如:
    Let’s go for a walk,shall we?
    Let’s forget it,shall we?
3.Let me和Let us 表示第二人称的祈使句,反意疑问句为“will you?”.如:
    Let us go for a walk,will you?
4.其它行为动词引起的祈使句,无论其陈述部分是否定还是肯定的祈使句,多用“will you?”,表一种客气的语气.如:
    Listen to me,will you?
    Don’t tell anyone about it,will you?
但在肯定的祈使句后有时也用“won’t you?”表“提醒对方注意”或表“邀请”.如:
    Have a cup of coffee,won’t you?
    Come in and take a seat,won’t you/will you?
祈使句用于两个重要句型中
1.“祈使句+and+表结果的陈述句”用来叙述肯定的条件.
2.“祈使句+or(else)+表结果的陈述句”用来叙述否定的条件,or(else)表示“否则;要不然”.试比较:
      Hurry up and you’ll catch the train.(=If you hurry up,you’ll catch the train.)
      Hurry up,or you’ll miss the train.(=If you don’t hurry up,you’ll miss the train.)
祈使句由直接引语变成间接引语
当祈使句由直接引语变成间接引语时,其常用结构为“ask/request/tell/order sb(not)to do sth”.
如:“Speak loudly,please!” the teacher said to me.(=The teacher asked me to speak loudly.)
     “Don’t smoke in the meeting room!” he said to Tom.(=He told Tom not to smoke in the meeting room.)