| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] they could [vb infin] be [vb pp] | 5 |
|
| 2 | [adv] they could have be [vb pp] | 5 |
|
| 3 | [adv] they could [vb infin] been [vb pp] | 5 |
|
