| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] [pron] could | 2700 |
|
| 2 | [vb past] [pers pn] could | 2608 |
|
| 3 | [vb past] they [vb mod] | 1415 |
|
| 4 | [vb past] they [modal v] | 1415 |
|
| 5 | [verb] they could | 629 |
|
| 6 | [vb past] they could | 330 |
|
| 7 | [vb past] they could | 327 |
|
