SN4 ""

No	Pattern	Freq
1	[pers pn] [vb mod] have been	7895
2	[pers pn] [modal v] have been	7670
3	it [modal v] have been	3771
4	[pers pn] would have been	2796
5	[pers pn] would have been	2466
6	[pers pn] must have been	1552
7	[pers pn] must have been	1552
8	he [modal v] have been	1266
9	[pers pn] might have been	979
10	[pers pn] might have been	979
11	[pers pn] could have been	975
12	[pers pn] could have been	975
13	they [modal v] have been	784
14	[pers pn] should have been	745
15	[pers pn] should have been	745
16	i [modal v] have been	686
17	[pers pn] may have been	663
18	[pers pn] may have been	663
19	she [modal v] have been	640
20	you [modal v] have been	393
21	[pers pn] 'd have been	330
22	we [modal v] have been	256
23	[pers pn] [modal v] 've been	182
24	[pers pn] will have been	130
25	[pers pn] will have been	105
26	them [modal v] have been	55
27	[pers pn] [modal v] to have been	42
28	[pers pn] ought have been	42
29	[pers pn] ought have been	42
30	[pers pn] 'll have been	25