1. but for [要不是；如果没有]
[构成]:but[但是] + for[为了；因为]
例句：But for your help, I would have failed. [要不是你的帮助，我就失败了。]

2. all but [几乎；差不多]
[构成]:all[所有] + but[除了]
例句：The job is all but finished. [这项工作几乎完成了。]

3. anything but [根本不；绝不]
[构成]:anything[任何事物] + but[除了]
例句：This dress is anything but beautiful. [这件连衣裙一点也不漂亮。]

4. nothing but [只有；仅仅]
[构成]:nothing[没有什么] + but[除了]
例句：He eats nothing but hamburgers. [他只吃汉堡包。]

5. can't but [不得不；只好]
[构成]:can't[不能] + but[但是]
例句：I can't but agree with you. [我不得不同意你。]

6. not only...but also... [不但...而且...]
[构成]:not only[不但] + but[而且] + also[也]
例句：She is not only beautiful but also intelligent. [她不但漂亮而且聪明。]

7. but then [不过；然而]
[构成]:but[但是] + then[然后；那时]
例句：I wanted to go, but then I changed my mind. [我想去，不过后来我改变主意了。]

8. none but [只有；除...外没有]
[构成]:none[没有人；没有任何东西] + but[除了]
例句：None but the brave deserve the fair. [只有勇敢的人才配得到美人。]

9. but yet [然而；但是]
[构成]:but[但是] + yet[然而；但是]
例句：He is poor but yet happy. [他很穷，但很快乐。]

10. last but not least [最后但同样重要的]
[构成]:last[最后的] + but[但是] + not[不] + least[最少；最小]
例句：Last but not least, I want to thank my family. [最后但同样重要的是，我要感谢我的家人。]

11. no sooner...than...but... [一...就...但是...]
[构成]:no sooner[一...就] + than[比] + but[但是]
例句：No sooner had I arrived than it started to rain, but I still went out. [我刚到就开始下雨了，但我还是出去了。]

12. every now and then but [时而；偶尔但]
[构成]:every now and then[时而；偶尔] + but[但是]
例句：Every now and then but I think of her. [我偶尔会想起她。]

13. more often than not but [往往；多半但]
[构成]:more often than not[往往；多半] + but[但是]
例句：More often than not but he fails to keep his promise. [他往往不能信守诺言。]

14. now and then but [不时；有时但]
[构成]:now and then[不时；有时] + but[但是]
例句：Now and then but I feel lonely. [我有时会感到孤独。]

15. here and there but [到处；处处但]
[构成]:here and there[到处；处处] + but[但是]
例句：I looked here and there but couldn't find my keys. [我到处找但找不到我的钥匙。]

16. up and down but [上上下下；来回但]
[构成]:up and down[上上下下；来回] + but[但是]
例句：He walked up and down but couldn't make a decision. [他走来走去但无法做出决定。]

17. far and wide but [到处；广泛地但]
[构成]:far and wide[到处；广泛地] + but[但是]
例句：The news spread far and wide but few people believed it. [这消息传遍了各地，但很少有人相信。]

18. by and by but [不久；迟早但]
[构成]:by and by[不久；迟早] + but[但是]
例句：By and by but he will understand. [迟早他会明白的。]

19. day in and day out but [天天；日复一日但]
[构成]:day in and day out[天天；日复一日] + but[但是]
例句：He works day in and day out but never complains. [他日复一日地工作，但从不抱怨。]

20. over and over but [一再；反复但]
[构成]:over and over[一再；反复] + but[但是]
例句：I told him over and over but he still made the same mistake. [我一再告诉他，但他还是犯了同样的错误。]