| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [was/were] impossible [to-vb] [Wh det] [noun] | 7 |
|
| 2 | [was/were] impossible [verb] [Wh det] [noun] | 7 |
|
| 3 | was impossible [verb] [Wh det] [noun] | 7 |
|
| 4 | [was/were] impossible [verb] what [noun] | 5 |
|
