| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [pron] could have | 5941 |
|
| 2 | what [vb mod] have | 623 |
|
| 3 | what [modal v] have | 623 |
|
| 4 | [Wh det] could have | 295 |
|
| 5 | what could [verb] | 166 |
|
| 6 | what could have | 79 |
|
| 7 | what could have | 79 |
|
