| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could have been [vb pp] at [adj] | 12 |
|
| 2 | could [vb infin] been [vb pp] at [det] | 9 |
|
| 3 | could [vb infin] been [vb pp] at any | 5 |
|
| 4 | could [vb infin] been [vb pp] at any | 5 |
|
