| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] [adv] [pron] could [adv] [vb infin] | 51 |
|
| 2 | [verb] [adv] they could [adv] [vb infin] | 18 |
|
| 3 | [vb past] [adv] they [modal v] [adv] [vb infin] | 16 |
|
| 4 | [vb past] [adv] they could [adv] [verb] | 7 |
|
