| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] not have noticed | 17 |
|
| 2 | [modal v] not have noticed | 17 |
|
| 3 | might not have noticed | 6 |
|
| 4 | may not have noticed | 6 |
|
| 5 | may not have noticed | 6 |
|
| 6 | might not have noticed | 6 |
|
| 7 | not have noticed [pron] | 5 |
|
