| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [to-vb] what [modal v] [vb infin] | 147 |
|
| 2 | [to-vb] what [vb mod] [vb infin] | 147 |
|
| 3 | [to-vb] [pron] could [vb infin] | 109 |
|
| 4 | [verb] what could [vb infin] | 38 |
|
| 5 | [to-vb] what could [verb] | 10 |
|
| 6 | [to-vb] what could [vb infin] | 10 |
|
