46)scratch the surface 只懂皮毛，很不了解(通常和限制性副词如only, hardly等词连用)
Model:
——You’ve certainly done a lot of research for your project. (你显然对你的课题做了不少研究。)
——It seems like a lot, but actually I’ve only scratched the surface. (看上去不少，但事实上我只懂一些毛皮。)

47)up in the air 尚未决定的；捉摸不定的；悬而未决的
Model:
——Her plans for the weekend are still up in the air. (她尚未决定如何度过这个周末。)

48)wear and tear 磨损；消耗
Model:
——Why do you always put on slippers when you go into your apartment? (为什么你老是一进公寓就穿上拖鞋？)
——It saves wear and tear on the carpet. (拖鞋不磨损地毯。)

49)with flying colors 大获全胜；胜利地
Model:
——How did Ellen do on her Ancient History exam? (Ellen古代史考得怎么样？)
——She passed with flying colors. (她考得好极了。)

50)get off on the wrong foot 开始就不顺利；一开始就犯了个错误
Model: [1995.5.]
——I hate to get off on the wrong foot. (我讨厌一开始就犯错误。)

51)get on someone’s nerves 使人不安，使人心烦
Model: [1996.8.]
——Why did you come to the meeting late? I left a message with your roommate about the time change. (为什么你开会迟到？我让你的同屋告诉你改时间的事了。)
——She has a very short memory and it really gets on my nerves sometimes. (她记性不好，有时真让我心烦。)

52)give someone a break 不要去管，饶了某人吧
Model: [1994.5.]
——Give me a break. I’m nervous enough as it is. (不要管我，我已经够紧张了。)

53)head and shoulders above (在…方面)强于某人
Model: [1991.10.]
——In computer programming, Susan is head and shoulders above the rest of us.(在计算机编程上，Susan比我们强。)

54)in the red 赤字，负债
Model: [1996.5.]
——So far the clubs are about three hundred dollars in the red, and we still have four months to go before membership renewal. ( 到目前为止，俱乐部有300元赤字，然而还有4个月才到交会员费的时间。)
——Well, we may have to raise our dues.(那么，我们必须提高会员费了。)

55)in the dark 一无所知；不了解情况
Model: [1994.1.]
——Do you have any idea what this notice is about? (你知道这通知讲的是什么吗？)
——I’m as in the dark as you are. (我也跟你一样不了解情况。)