| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [pron] could | 87089 |
|
| 2 | [Wh det] [vb mod] | 43219 |
|
| 3 | [Wh det] [modal v] | 43219 |
|
| 4 | [Wh det] could | 4543 |
|
