SN4 ""

No	Pattern	Freq
1	but not [conj]	271
2	but not [subord]	240
3	but not before	78
4	but not before	78
5	but not if	42
6	but not if	42
7	but not as	30
8	but not as	30
9	but not because	29
10	but not that	29
11	but not that	29
12	but not because	29
13	but not [that]	29
14	but not until	25
15	but not until	25
16	but not when	12
17	but not when	12
18	but not while	8
19	but not while	8