12 at sb‘s service 愿为某人服务
I am at your service at any time.
13 around the clock 24小时不停
Martha studied around the clock for management exam.
14 as far as I know 就我所知
15 at home with 对………很熟悉
She is at home with problems like this.
16 back out
1) 退出
A： Wasn‘t Bert supposed to sing tonight?
B： Yes， but he backed out at last minute
2)不履行
She finally backed out of her promise.
17 be cut out for 天生适合
I‘m not cut out to be a hero.
18 be absorbed in
She has been absorbed in a horror fiction. I can‘t tear her away.
19 be addicted to 对……上瘾
She has been addicted to drugs for years.
20 be attached to 对……有感情
A： I‘m amazed that you are still driving that old car of yours. I thought you would have gotten rid of it years ago.
B： It runs well and I‘ve actually been quite attached to it.
21 back up
1) 累积
The subway is running behind schedule， and traffic is backed up for blocks. I don‘t know if we’ll make the 6：30 show.
2) 支持
I‘ll back it up.
22 be bound for 到……地方
The bus is bound for New England.
23 be (feel) myself 找到自我
I‘m feeling myself again.
24 be burned up 生气
She was really burned up at the news.
25 be hard up for
I‘m hard up for clothes， but I have a lot of books.
