SN4 ""

No	Pattern	Freq
1	may have been [adj]	548
2	may have been [adj]	548
3	may have been [adj]	452
4	may have been [det]	49
5	may have been [num]	34
6	may have been due	29
7	may have been due	29
8	may have been responsible	24
9	may have been responsible	24
10	may have been able	23
11	may have been able	23
12	may have been one	19
13	may have been one	19
14	may have been some	18
15	may have been some	18
16	may have been involved	13
17	may have been involved	13
18	may have been [adj -er]	11
19	may have been different	11
20	may have been present	11
21	may have been present	11
22	may have been true	11
23	may have been true	11
24	may have been different	11
25	may have been this	6
26	may have been this	6