| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | they could [adv] [vb infin] | 600 |
|
| 2 | [vb past] they could [vb infin] | 182 |
|
| 3 | [vb past] they [adv] [vb infin] | 80 |
|
| 4 | [vb past] they could [adv] | 31 |
|
| 5 | [vb past] could [adv] [vb infin] | 11 |
|
