SN4 ""

No	Pattern	Freq
1	[adj] [conj] it have been [prep]	85
2	[noun] [conj] it have been [prep]	56
3	[noun sg] [conj] it have been [prep]	49
4	[adj] [conj] it have been [prep]	43
5	[verb] [conj] it have been [prep]	27
6	[adj -er] [conj] it have been [prep]	27
7	[adv] [conj] it have been [prep]	24
8	[adv] [conj] it have been [prep]	22
9	[vb pp] [conj] it have been [prep]	9
10	[det] [conj] it have been [prep]	9
11	[conj] [conj] it have been [prep]	8
12	[num] [conj] it have been [prep]	6
13	[vb past] [conj] it have been [prep]	6
14	[be] [conj] it have been [prep]	5
15	be [conj] it have been [prep]	5
16	high [conj] it have been [prep]	5
17	[conj] [conj] it have been [prep]	8
18	[conj] [subord] it have been [prep]	8
19	[conj] it [vb mod] have been [prep]	65
20	[conj] it [modal v] have been [prep]	65
21	[conj] it would have been [prep]	23
22	[conj] it would have been [prep]	23
23	[conj] it must have been [prep]	11
24	[conj] it must have been [prep]	11
25	[conj] it may have been [prep]	10
26	[conj] it may have been [prep]	10
27	[conj] it could have been [prep]	8
28	[conj] it should have been [prep]	8
29	[conj] it should have been [prep]	8
30	[conj] it could have been [prep]	8