请问set out、set about、set off各是什么意思，你能为我造句子吗

set out出发

They set out on the last stage of their journey.
他们开始了旅行的最后一程.
She set out at dawn.
她天一亮就动身了.

set about: 开始,着手

1. You must set about your work at once.
你必须立即开始工作。
2. Do you know how to set about going on this work?
你知道怎样着手进行这项工作吗？

set off=set out出发

If you want to catch that train we'd better set off for the station immediately.
你要是想赶上那班火车，咱们就最好马上动身去火车站。
What time are you planning to set off tomorrow?
你打算明天几点钟启程?

set about:
开始,着手；攻击
As soon as she arrived she set about tidying up the room.她一到，就开始收拾房间。
The little fellow rolled up his sleeves and set about the bully.小家伙卷起他的袖子向暴徒进攻。
set off:
动身，出发；引起；装饰，点缀；使...爆发
We will set off for the factory tomorrow.我们明天打算去工厂。
set out:
动身，出发；打算，企图；表达，发表
The boys plan to set out for Tianjin next week.
孩子们计划下星期动身去天津。

楼上的各位已经把意思说清楚了，如果你是为了做题的话，还有要注意的地方,因为考试能用到的区