53. He is taller than I by a head.　 by a river 在…旁边　 by sea/air/land

by the way 顺便问一句　 by way of 取道　 by means of 通过　 by all means 尽一切办法， by no means 决不　 lead sb by the hand 牵住…的手　　　 pay sb by the hour 按小时付费

by hand 手工 by far+最高级　 make a living by doing (谋生)by turns = in turn = in one's turn

52. but for 要不是+n.+虚拟从句 (But for your help, I wouldn't have succeeded.)

not only…but also　 not...but... 不是…而是… nothing but 只不过，仅仅　　

anything but 一点也不　　　 none but　 只有　　　　　　 He chose none but the best.

51. do nothing/anything but do　　

have no choice but to do　　

can't (help) but do 不得不…

50. be busy in doing = be busy with sth　 忙于　　　 be busy at work

49. be on business , be on holiday/vacation/leave 度假　 , follow a business of 以…为业

It's none of your business. = Mind your own business. 这不关你的事。

48. burst into laughter = burst out laughing 哈哈大笑　 burst into tears = burst out crying 大哭