| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [conj] [ex0] could have been [det] | 7 |
|
| 2 | [conj] [ex0] could [vb infin] been [det] | 7 |
|
| 3 | [conj] there could [verb] been [det] | 7 |
|
| 4 | [conj] [ex0] could have been [det] | 7 |
|
