| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [vb infin] [pers pn] [adv] | 1219 |
|
| 2 | [modal v] [vb infin] [pers pn] [Wh adv] | 427 |
|
| 3 | could [vb infin] [pron] [Wh adv] | 35 |
|
| 4 | could [verb] [pers pn] [Wh adv] | 33 |
|
