| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] [pron] could [verb] | 3802 |
|
| 2 | [Wh adv] [pron] could [verb] | 765 |
|
| 3 | why [pron] [modal v] [verb] | 688 |
|
| 4 | why [pron] [vb mod] [verb] | 688 |
|
| 5 | why [pron] could [verb] | 10 |
|
| 6 | why [pron] could [verb] | 10 |
|
