SN4 ""

No	Pattern	Freq
1	it [modal v] have been [prep] [adj]	44
2	it [vb mod] have been [prep] [adj]	44
3	it [modal v] have been [prep] [adj]	43
4	it [modal v] have been [prep] [det]	31
5	it must have been [prep] [adj]	20
6	it must have been [prep] [adj]	20
7	it would have been [prep] [adj]	11
8	it [modal v] have been in [adj]	11
9	it [modal v] have been in [adj]	11
10	it would have been [prep] [adj]	11
11	it [modal v] have been [prep] this	10
12	it [modal v] have been [prep] this	10
13	it [modal v] have been [prep] [num]	7
14	it [modal v] have been [prep] that	7
15	it may have been [prep] [adj]	7
16	it [modal v] have been [prep] that	7
17	it may have been [prep] [adj]	7
18	it [modal v] have been like [adj]	6
19	it [modal v] have been like [adj]	6
20	it [modal v] have been [prep] [adj]	5