SN4 ""

No	Pattern	Freq
1	[vb mod] not have been for	6
2	[modal v] not have been for	6
3	could not have been for	5
4	could not have been for	5
5	not have been [adj] for	43
6	not have been [adj] for	38
7	not have been [verb] for	19
8	not have been [vb pp] for	14
9	not have been easy for	9
10	not have been easy for	9
11	not have been possible for	7
12	not have been good for	7
13	not have been possible for	7
14	not have been better for	5
15	not have been [v-ing] for	5
16	not have been [adj -er] for	5