同学你好，该知识点来自沪江网校《新概念英语第四册【天猫专享】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好~
是have sth done
have sth done既可以表示“（主语）请/派别人完成某事”也可以表示“（主语）完成某事（可能参与）”，具体要看上下文。其中sth是被……的，是动作的承受者。
We had the machine repaired.  我们请人把机器修好了。
They are going to have some threes planted.他们打算植些树。

have sb do是“让某人/某事做”，其中sb是主动做某事。
The boss often has them work for 14 hours a day.
老板经常要他们一天工作14 个小时。

have sb doing 让某人一直做某事
The boss had his workers working all day long. 那老板让工人们整天（不停地）干活。

祝同学学习进步~