SN4 ""

No	Pattern	Freq
1	[noun] may have been [prep] [adj]	15
2	[pron] may have been [prep] [adj]	14
3	[pers pn] may have been [prep] [adj]	8
4	it may have been [prep] [adj]	7
5	it may have been [prep] [adj]	7
6	[noun sg] may have been [prep] [adj]	7
7	[noun pl] may have been [prep] [adj]	5
8	may [adv] have been [prep] [adj]	18
9	may [adv] have been [prep] [adj]	12
10	may not have been [prep] [adj]	6
11	may [not/n't] have been [prep] [adj]	6
12	may not have been [prep] [adj]	6
13	may have been [verb] [prep] [adj]	91
14	may have been [vb pp] [prep] [adj]	88
15	may have been [adj] [prep] [adj]	51
16	may have been [adj] [prep] [adj]	47
17	may have been [noun] [prep] [adj]	6
18	may have been involved [prep] [adj]	5
19	may have been due [prep] [adj]	5
20	may have been involved [prep] [adj]	5
21	may have been due [prep] [adj]	5
22	may have been [prep] [art] [adj]	15
23	may have been [prep] [art] [adj]	15
24	may have been [prep] the [adj]	11
25	may have been [prep] the [adj]	11
26	may have been [prep] [adj] [adj]	5
27	may have been [prep] [adj] [noun]	21
28	may have been [prep] [adj] [noun sg]	18
29	may have been [prep] [adj] [adj]	5