| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | may not have been [adj] | 68 |
|
| 2 | may have been [prep] [adj] | 33 |
|
| 3 | not have been [prep] [adj] | 18 |
|
| 4 | may not have been [prep] | 15 |
|
