祈使句所能表达的含义：命令：Make your bed at once! 马上把床铺好！禁止：Don’t touch! 不要碰！请求，恳求：Shut the door, please. 请关门。 Help! 救命！忠告，劝告：Lock the door before you go to bed. 睡觉前把门锁上。建议，指示：Let’s have a party! 咱们举行个聚会吧。 Take the first street on the left.走右边第一条街。邀请：Make yourself at home! 请自便（别客气） Come in and sit down. 进来坐。 Help yourself to some fruit. 吃点水果。提供：Have some orange juice. 喝点橙汁吧。祝愿：Have a good time! 祝你（过得）愉快！警告，威胁：Look out! 当心！ Do that again and you will be in trouble! 你在那样做会倒霉的！允诺：Finish your homework and I’ll buy you some food.做完作业就给你买吃的。诅咒：Go to hell! 滚！自忖：Let me see now. 让我考虑考虑。