11. allergic to 對……過敏
　　Oh man! Something in this room is making my eyes itch, I must be allergic to something.
　　12. at sb’s service 愿為某人服務(wù)
　　I am at your service at any time.
　　13. around the clock 24小時不停
　　Martha studied around the clock for management exam.
　　14. as far as I know 就我所知
　　As far as I know, we will have a test next Monday.
　　15. at home with 對…..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 天生適合
　　I’m not cut out to be a hero.
　　18. be absorbed in 沉浸在……
　　She has been absorbed in a horror fiction. I can’t tear her away.
　　19. be addicted to 對……上癮
　　She has been addicted to drugs for years.
　　20. be attached to 對……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.