| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] have seen a | 30 |
|
| 2 | may have seen a | 8 |
|
| 3 | may have seen a | 8 |
|
| 4 | would have seen a | 6 |
|
| 5 | must have seen a | 6 |
|
| 6 | must have seen a | 6 |
|
| 7 | would have seen a | 6 |
|
